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Chemistry Articles & Features

This is an index of all of the original chemistry articles and features written by Anne Helmenstine, Ph.D. for About Chemistry.

-ology List of Sciences
An -ology is a discipline of study, as indicated by having the -ology suffix. This is a list of science ologies.

10 Carbon Facts
Learn some interesting facts about carbon, the element that is the basis for organic chemistry.

10 Nitrogen Facts
Get handy facts for the element nitrogen.

10 Oxygen Facts
Learn some interesting facts about the element oxygen.

10 Polonium Facts
Before Russian ex-spy Alexander Litvinenko was poisoned with polonium, few people had even heard of it. Here are ten facts about this interesting element.

2001 Chemistry Features
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2001. Learn about snowflakes, preservatives, how soap cleans, how firework colors work, and whether or not it's possible to turn lead into gold.

2002 Chemistry Features
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2002.

2003 Chemistry Features
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2003.

2004 Chemistry Articles
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2004.

2005 Chemistry Articles
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2005.

2007 Chemistry Features
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2007. Learn about the invention of fireworks, make fake snow, set up a home chemistry lab, learn how chemical weapons smell, and find a science fair project idea.

2008 Chemistry Features
This is a collection of chemistry features written by Anne Helmenstine for About Chemistry in 2008.

6th Grade Science Fair Projects
Get ideas for 6th grade science fair projects. These are topics and experiments suitable for upper grade school or entry level into middle school.

7th Grade Science Fair Projects
Find an idea for a 7th grade science fair project or a science project targeted at the intermediate middle school level.

About.com Chemistry on Facebook and Twitter
You can follow About.com Chemistry on Facebook and Twitter. Here's how to interact with Anne Helmenstine of About.com Chemistry and some information about what to expect from Facebook and Twitter.

Absinthe Chemistry
Absinthe has been enjoying a resurgence in popularity, as countries lift the ban on making the green wormwood and anise-flavored spirit. Learn about the history of the liqueur, why it was banned, a bit about its chemistry, how to make absinthe, and how to drink it.

Alchemical Symbols of the Elements
See the symbols of the elements and learn how alchemists used them.

Alchemy Symbols
See the alchemical symbols for the chemical elements.

Alfred B. Nobel Prizes in Chemistry
This is a list of all of the Nobel laureates in Chemistry. The year, winner name(s), country, and research are included. Links to additional information on the laureates and Nobel foundation are also provided.

Alfred Bernhard Nobel (1833 - 1896)
Chemist and inventor of dynamite. Creator of the Nobel Foundation.

All About Earth Day
Are you wondering what Earth Day is, when it's celebrated, and what people do on Earth Day? Here are the answers to your Earth Day questions!

Alphabetical List of Elements
Here's a list of the elements, in alphabetical order according to their IUPAC names.

AMCAS Application for Medical School
Get information about the AMCAS (American Medical College Application Service) application for medical school. Tips are included to help you make your application the best it can be!

Amedeo Avogadro
Looking for information about Amedeo Avogadro, Avogadro's Hypothesis, and Avogadro's Number? It's all here, including a picture of Avogadro and links to other Avogadro and History of Chemistry web sites.

Ammonium Phosphate Crystals (Easy)
Monoammonium phosphate crystals are among the quickest, easiest, and safest crystals you can grow. Learn how to grow these crystals yourself.

Anabolic Steroids
Learn what anabolic steroids are, how they can enhance athletic performance, and what risks are associated with using performance enhancing drugs.

Applying to Medical School - What to Do if You're Rejected
Most applicants to medical school don't get accepted! Make plans for this possibility. Here is advice on what to do if your application is rejected, with concrete steps to improve your application for the next year.

Aqueous Solution Dilution
Here is a worked example of how to calculate a dilution of a stock solution.

Area, Perimeter & Volume Formulas
Perimeter, surface area and volume formulas are used for many chemistry calculations. You may need to find surface area and volume to determine density and concentration, for example. While it's a good idea to memorize these formulas, here a list of formulas to use as a handy reference.

Atom Hangman Game
All of the words in this hangman game relate to atoms or parts of atoms. It's a fun and easy way to test your grasp of some elementary chemistry terms and concepts.

Atomic Structure Quiz
This ten question multiple choice quiz tests your comprehension of the electric nature of atoms, components of atomic structure, oxidation numbers, valence, quantum numbers, electron configuration, and Lewis dot structures.

Atomic Weights of the Elements
This is the list of the atomic weights of the elements (2007 IUPAC-accepted values). Elements are listed in order of increasing atomic number.

Atoms and Atomic Theory - Study Guide
Get essential facts about atoms and the basics of atomic theory, work problems to test your skills, then take a quiz to make sure you understand the concepts.

Aufbau Principle and Electronic Structure
Stable atoms have as many electrons as they do protons. How do these electrons orient themselves around the nucleus? They fill their electron orbitals by the aufbau principle.

Baggie Chemistry - Experiment with Chemical Reactions
Introduce students to chemical reactions and experimentation using common materials and baggies.

Baking Ingredient Substitutions
Do you need to replace one ingredient with another in a recipe? This is a table of ingredient substitutions that you can make when baking.

Baking Soda & Vinegar Chemical Volcano
Making a baking soda and vinegar volcano is safe and easy, plus it only requires a few inexpensive kitchen ingredients. Here are detailed instructions for making a volcano, plus a look at the chemical reactions involved.

Baking Soda & Vinegar Foam Fight
This is a twist on the classic baking soda volcano, where you use the ingredients to make squirt-able fountains of foam.

Baking Soda Stalactites and Stalagmites
Make your own stalagmites and stalactites using baking soda or sodium bicarbonate. It's an easy, non-toxic crystal project.

Balancing Chemical Equations
Here is a step-by-step tutorial for balancing chemical equations, along with a worked example. This is a must-read for students of general and introductory chemistry!

Balancing Redox Reactions
Get step-by-step instructions for balancing redox reactions for conservation of mass and charge in electrochemistry.

Barking Dog Reaction
The Barking Dog chemistry demonstration is based on an exothermic reaction between nitrous or nitric oxide and carbon disulfide. Ignition of the mixture results in a bright blue chemiluminescent flash accompanied by a characteristic barking sound.

Basic Model of the Atom
Are you confused about atoms, elements, protons, neutrons, electrons, isotopes, and ions? Here's a basic look at the model of the atom. It's a great overview for kids or anyone looking to grasp the essentials of atomic theory.

Basics of Acids and Bases Quiz
How well do you understand the basic concepts of acids, bases, and pH? Here's a ten question multiple choice and true/false quiz you can take to test yourself.

Bathroom Chemistry Quiz
Do you know about the chemistry of excretion and toiletries? Let's find out! Take this multiple choice quiz and test your bathroom knowledge.

Before You Buy a Chemistry Set
Getting a child a chemistry set is an excellent way to introduce principles of chemistry. However, not all chemistry sets are created equal. Check out these tips about age recommendations, supervision and safety, replacement chemicals, and prices.

Before You Buy a Chemistry Textbook
Asking yourself some questions can save a lot of money at the bookstore! Find out what you need to know before you purchase a chemistry textbook. The article refers to chemistry, but the tips really apply to all texts.

Before You Buy a Rock Tumbler
Learn about the two main types of rock tumblers and get some selection tips and helpful advice to prepare for your first tumble. Links to related resources and support sites are also included.

Before You Buy Gasoline
This is a guide to help you choose the best gasoline for your auto, with quick 'what you need to know' facts. There is information about octane ratings, additives, reformulated and leaded fuel, and links to sites offering complementary or comprehensive information.

Bend Water with Static Electricity
Use static electricity to bend a stream of flowing water. This is an easy science activity that illustrates how opposite electrical charges attract each other.

Best Science Toys
The best toys never go out of style. Telescopes, rock tumblers, creature habitats, and chemistry kits are as educational as ever. The latest versions are safer and more interesting than ever before.

BHA and BHT - Food Preservative Chemistry
Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are added to many foods to prevent fat spoilage. This article describes what BHA and BHT are, what they do, and how they do it. There is a fairly lengthy list of references because there is controversy over the health effects of BHA, BHT, and other additives.

Biochemistry of Lycopene
Lycopene is the red pigment in tomatoes and several fruits. Find out more about how this antioxidant protects against cancer and heart disease.

Biodiesel from Vegetable Oil Tutorial
As the price of diesel continues to climb, you may wish to consider making your own diesel from cooking oil, called biodiesel. It's easy and could save you money.

Black Chemists & Chemical Engineers
Black scientists, engineers, and inventors have made important contributions to the science of chemistry. Learn about black chemists and chemical engineers and their projects. The focus is on African American chemists, but black scientists from other countries are included.

Black Snakes or Glow Worms
You can make black snake or glow worm fireworks yourself, safely and easily.

Blue Bottle Color Change Demonstration
Learn how to perform the blue bottle chemistry demonstration, in which a blue liquid becomes clear, then returns to blue when swirled around. Instructions are also given for red -> clear -> red and green -> red -> green reactions.

Bohr Model of the Atom
The Bohr Model has an atom consisting of a small, positively-charged nucleus orbited by negatively-charged electrons. Here's a closer look at the Bohr Model, which is sometimes called the Rutherford-Bohr Model.

Bonds & Compounds Quiz
This ten question multiple-choice quiz will test your understanding of the types of chemical bonds, how electrons are transferred between elements in a compound, and how compounds form.

Bravais Crystal Lattices
There are 14 distinct Bravais crystal lattices. The lattices can be used to describe the geometrical symmetry of a crystal. The Bravais lattices are sometimes called space lattices.

Briggs-Rauscher Oscillating Color Change Reaction
The Briggs-Rauscher reaction, also known as 'the oscillating clock', is one of the most common demonstrations of a chemical oscillator reaction. Three colorless solutions are mixed together, producing a mixture that oscillates between clear, amber, and deep blue.

Bubble Life & Temperature
This science fair project examines whether bubbles last the same length of time in hot temperatures as they do in cool temperatures.

Bubble Prints
Bubble prints are like fingerprints, except made with bubbles. You can make bubble prints and learn about how bubbles are shaped and how pigments combine to make different colors.

Buffers are an important concept in acid-base chemistry. Here's a look at what buffers are and how they function.

Burning Bubbles Project
Bubbles are fun no matter what, but bubbles you can burn just has that added extra appeal. Here's an easy science project you can do that proves propellants in common products are flammable and allows you to burn some bubbles.

Burning Money Chemistry Demonstration
Set money on fire and watch it burn out without damaging the bill. This is a nice magic trick, based on everyday chemistry.

Caffeine Chemistry
Learn about the chemical and biological properties of caffeine, the methylxanthine stimulant found in coffee and other foods.

Caffeine Science Fair Projects
Caffeine is a naturally occurring stimulant that is found in many foods, beverages, and drugs. You can explore the effects of caffeine with your science fair project.

Calcium Copper Acetate Hexahydrate Crystals
Grow blue tetragonal crystals of calcium copper acetate hexahydrate.

Calculating Concentration
Do the units for solution concentration confuse you? Get definitions and examples for calculating percent composition by mass, mole fraction, molarity, molality, and normality. I've also included a bit of information on dilutions.

Can a Candle Burn in Zero Gravity?
Can a candle burn in the absence of gravity? Here's the answer to this frequently asked question about fire.

Can You Drink Too Much Water?
It's important to drink plenty of fluids, but can you overdo it? Learn the truth about water intoxication and hyponatremia.

Can You Use Laundry Detergent in the Dishwasher?
Yes, you could put laundry detergent in your dishwasher. Should you? Probably not. Here's why.

Can Your Hair Turn White from Fright or Turn Gray Overnight?
Is it true your hair can turn white from a bad scare or that your hair can turn gray overnight? Learn about your haircolor and get the answer to the question.

Candy Triboluminescence
Wintergreen Lifesavers aren't the only candies that can make a spark in the dark. Take an in-depth look at the mechanism behind this special chemiluminescence caused by friction.

Carbohydrates or saccharides are the most abundant class of biomolecules. Carbohydrates are used to store energy, though they serve other important functions as well. This is an overview of carbohydrate chemistry, including a look at the types of carbohydrates, their functions, and carbohydrate classification.

Carbon 14 Dating
Here's a worked example of the calculation for carbon 14 dating of organic material. The same principle can be applied to other isotopic ratios used to estimate age.

Carbon Cycle
Carbon is an element that is essential for life. The carbon cycle describes the storage and exchange of carbon between the Earth's biosphere, atmosphere, hydrosphere, and geosphere.

Carbonated Fizzy Fruit
Use dry ice to carbonate fruit. The fruit will be filled with tingly carbon dioxide bubbles, like a soda. The fizzy fruit is great to eat on its own or it can be used in recipes.

Chalk Chromatography
You can use chalk and alcohol to perfom chromatography to separate the pigments in food colorings or inks. After you've finished making your chromatogram, you'll have colored chalk.

Chemical & Physical Changes
Find out what chemical and physical changes are, get examples, and learn how to tell them apart.

Chemical Engineer
This is a job profile and career information for a chemical engineer.

Chemical Engineering Courses
Are you interested in studying chemical engineering? Here's a look at some of the courses chemical engineering students are expected to take in college.

Chemical Reaction Orders
Learn how to classify chemical reactions using kinetics. Identify and define zero, first, second, mixed, and higher order reactions.

Chemical Weapons and Warfare Agents
Get basic information about chemical weapons and learn what you can do to protect yourself in the event of a chemical attack.

Chemical Weapons
See the chemical structures of chemical weapons and warfare agents and learn a little about their uses.

Chemical, Physical, and Nuclear Changes Quiz
Do you understand the differences between the types of changes and the concepts associated with these reactions? Here's a ten question quiz you can take to test your knowledge.

Chemicals for Hangovers
A hangover is Nature's way of reminding you that alcohol is not good for your body. Having said that, there are some substances that will reduce the damage or lessen the discomfort.

Chemist Profile
Take a look at what a chemist is, what a chemist does, and what type of salary and career opportunities you can expect as a chemist.

Chemistry Basics - What Is Chemistry
Start learning chemistry with the basics. Learn what chemistry is, what chemists do, and why it's important to study chemistry.

Chemistry Fun with Pennies
Use pennies, nails, and a few simple household ingredients to explore some of the interesting properties of metals. Clean the pennies chemically, make verdigris, and plate the nails with copper.

Chemistry Laboratory Safety Rules
Make your chemistry laboratory experience safe by following these simple rules.

Chemistry of Autumn Leaf Color
Why do leaf colors change in the fall? What causes the different colors? It's mostly a matter of photochemistry rather than of temperature. Find out more!

Chemistry of Counterterrorism
Learn how chemistry is used in the war against terrorism. Topics include forensic science, sampling, detection, countermeasures, and use of dogs. There are links to centers specializing in counterterrorism and to government agencies.

Chemistry of Diamond
Part I: Carbon Chemistry and Diamond Crystal Structure. Part II: Properties and Types of Diamonds. There are also links to learn about carbon allotropes, diamond mining, diamonds as gemstones, and geology.

Chemistry of Firework Colors
Fireworks combine art and science. This article focuses on the chemistry behind firework colors, including the mechanisms of color production and a table listing colorants. There are links to websites about fireworks - some with instructions for making your own!

Chemistry of Hard and Soft Water
Do you have hard water or soft water? Both? Do you know why? Get the definitions for hard and soft water, learn about their chemistry, and examine the pros and cons of each type of water.

Chemistry of Smoke Machines
Have you ever wondered how smoke machines work or wanted to make your own smoke or fog? Here's your chance to find out how it works. There are separate sections for each type of non-toxic smoke generator, together with important safety tips.

Bubble Science
Learn about the science behind bubbles. Find out what bubbles are and how they behave.

Chemistry of Theobromine
The primary methylxanthine in chocolate is theobromine, a molecule similar to caffeine. See the structure of theobromine and read about its chemistry, effects on people and animals, and uses. There are links to chocolate history and chemical research, veterinary advice for theobromine poisoning, and related resources.

Chemistry Questions You Should Be Able to Answer
These are questions an educated person should be able to answer relating to chemistry in the everyday world.

Chemistry Scavenger Hunt
A chemistry scavenger hunt is an educational game where you find items that match a description. It's a great way to learn key concepts. Here's a list of chemistry scavenger hunt clues and items that match.

Chemistry Science Fair Project Ideas
Stimulate your own ideas for a chemistry science fair project by looking at examples of chemistry projects other students have performed.

Chemistry Study Tips
Here are some homework and study tips to help you succeed in chemistry.

Chemistry Timeline
Find out who did what and when they did it. This timeline chronicles achievements in chemistry and in other disciplines (e.g., physics, mathematics) as they apply to chemistry.

Chemistry Trivia Quiz #2
This quiz is designed to trip up a middle school chemistry student. It focuses on everyday chemistry rather than simple textbook facts. Can you get a perfect score?

Chemistry Trivia Quiz
Here's a ten question multiple choice quiz to test your understanding of general chemistry concepts. I'd rate it 'easy'. Are you up for the challenge?

Christmas Tree or Floral Preservative Recipe
Is there a secret special ingredient in those little packets of floral preservative? No! It's easy and economical to make your own Christmas tree or cut flower preservative, using ingredients found at home.

Chromatography with Candy and Coffee Filters
Analyze the dyes used in your favorite candies with paper chromatography using a coffee filter, colored candies, and a salt solution.

Citric Acid Cycle
The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, is a series of chemical reactions in the cell that breaks down food molecules into carbon dioxide, water, and energy.

Classic Chemical Volcano
Here are the instructions for making the classic chemical volcano. This demonstration uses ammonium dichromate to produce 'Vesuvius fire', with glowing sparks and a cone of deep green ash.

Cocaine Facts
Learn what cocaine or coke is, why people take cocaine, how it's made, and what risks are associated with using cocaine.

College Essentials
Science majors need items above and beyond general college supplies. Check out these top picks and compare prices online. If you wait to buy them at the college bookstore you will pay a premium!

College Science Fair Projects
Get ideas for science fair projects suitable for college level students. Most of these project are targeted for the freshman year.

Colored Flowers
It's easy to make your own colored flowers, especially carnations and daisies, but there are a couple of tricks that help ensure great results. Here's how you do it.

Colored Glass Chemistry
Have you ever wondered how glass is colored? Here's a table of common colorants and a description of processes used to color glass.

Colored Smoke Recipes
Colored smoke is easy to make and requires few ingredients. Here's a list of some colored smoke formulations to try.

Colored Soap Bubbles
Make brightly colored pink and blue soap bubbles that won't stain clothing or surfaces.

Common Household Chemicals - Dangerous Mixtures
Labs have lists of chemicals that don't go together, but it isn't as easy to avoid dangerous mixtures with home chemicals because they aren't pure substances. Here's some help. Be safe and don't mix these common household chemicals.

Compound Names Chemistry Quiz
This brief multiple-choice test will help you see if you know how to name compounds.

Compounds - Inorganic Chemicals
List of inorganic chemical compounds.

Copper Plating Christmas Ornament
Copper plate a holiday decoration as a Christmas ornament or for other decorative uses.

Copper Sulfate Crystals
Copper sulfate crystals are among the easiest and most beautiful crystals that you can grow. The brilliant blue crystals can be grown relatively quickly and can become quite large. Here's how you can grow copper sulfate crystals yourself.

Crack Cocaine Facts
Learn what crack cocaine is, why people take crack, how it's made, and what risks are associated with using crack cocaine.

Crystal Geode Project
Natural geodes are hollow rock formations that contain deposits of crystals. Assuming you don't have a geological timeframe to obtain a geode, it's easy to make your own crystal geode using plaster of paris, alum, and food coloring.

Crystal Growing Kits
Here are some kits for growing your own crystals. There are big kits with multiple crystal types, non-toxic kits for younger explorers, pre-sealed crystal globes, and unopened geodes!

Crystal Growing Quiz
Are you an ace at growing your own crystals? Test your knowledge about seed crystals, the factors that affect crystal growth, and crystal types with this fun multiple choice quiz.

Crystal Meth Facts
Learn what crystal meth is, why people take crystal meth, how it's made, and what risks are associated with using methamphetamine.

Crystal Photo Gallery
This is a collection of photographs of crystals. Some are crystals you can grow yourself. Others are representative pictures of crystals of elements and minerals.

Crystal Types - Shapes & Structures
Let's take a look at the two main ways to categorize crystal types. I've described the major crystal structures (e.g., triclinic, hexagonal) and how crystals are classified by their properties (e.g., ionic, covalent) and provided links so that you can see examples of crystal types and learn more about crystallography.

Cup of Quick Crystal Needles
Grow a cupful of epsom salt crystal needles in your refrigerator. It's quick, easy, and safe.

Curiosity Kits Neon and Glow Magic Powerballs - Review
Magic Powerballs are polymer bouncy balls that anyone ages 6 and up can make. My kids and I gave this project a try. Here is what we thought of the Magic Powerballs kit.

Cut Flower Preservative Recipes
It's easy and economical to make your own cut flower preservative. Adding floral preservative will help keep your flowers beautiful much longer than if you simply filled a vase with water.

Dalton's Law Calculation
Dalton's Law of Partial Pressures, or Dalton's Law, states that the total pressure of a gas in a container is the sum of the partial pressures of the individual gases in the container. Here is a worked example problem showing how to use Dalton's Law to calculate the pressure of a gas.

Dancing Gummi Bear Demonstration
Place a Gummi Bear candy into a test tube containing molten potassium chlorate and watch it dance amidst purple flames. This stunning demonstration is an example of a strongly product-favored reaction, plus it's a lot of fun.

DEET Chemistry
Learn about the insect repellent called DEET. See its chemical structure, find out how it works, get information about the risks of using DEET, and find out how to reduce your need for bug spray.

Density Column
Make a liquid layers density column with as many as seven layers using common household liquids. This is an easy, fun and colorful science project that illustrates the concepts of density and miscibility.

Disappearing Ink Instructions
Learn how to make blue or red ink that will disappear after exposure to air. Tips for restoring the color and an explanation of the acid-base chemistry of the reaction are also included.

Diving Ketchup Magic Trick
Place a ketchup packet in a bottle of water and make it rise and fall at your command, as if by magic. Of course, the magic involves some basic science. Here's how to do the diving ketchup trick and how it works.

Dmitri Mendeleev (1834 - 1907)
Dmitri Mendeleev formulated a periodic table similar to the one we use today. Elements were grouped according to recurring trends in their properties.

Do You Add Sulfuric Acid to Water or Water to Sulfuric Acid?
It's important to add sulfuric acid to water and not water to concentrated sulfuric acid. Here's an explanation of why you don't want to make a mistake and some mnemonics that might help you remember how to play it safe in the chemistry lab.

Do You Burn More Calories when you Think Hard?
Find out how many calories you burn when thinking and how it compares with the energy expended by physical exercise.

Does Eating Turkey Make You Sleepy?
Find out why everyone wants to take a nap after Thanksgiving Day turkey dinner. Let's talk turkey and learn about L-tryptophan and carbohydrate metabolism.

Drug Paraphernalia
Would you know drug paraphernalia if you saw it? This is a collection of photos of drug paraphernalia.

Drug Photo Gallery
See the molecular structures of common drugs, including drugs of abuse. Photos of the drugs themselves are also included.

Drugs from Plants
This is a table listing many of the pharmaceuticals that are derived from plants, including the names of the drugs, their actions, plant sources, and the common names of the plants.

Dry Ice Bubble
The giant bubble you can make using dry ice and bubble solution sort of resembles a crystal ball. This is an easy and spectacular science project.

Dry Ice Facts
Dry ice is solid carbon dioxide. Here are some facts about dry ice that can help keep you safe when working with it, plus are just fun to know.

Dry Ice Science Fair Projects
There are a lot of interesting science fair projects you can do using dry ice. Here are some ideas that you can use as-is or can modify to make your own unique science fair project.

Effect of Acids and Bases on the Browning of Apples
Perform an experiment to observe the effects of acids, bases, and water on the rate of browning of cut apples or other produce.

Egg in a Bottle Demonstration
You don't see air and might not think much of it is contained in a bottle, but air and the pressure it exerts can be very powerful. The egg in a bottle demonstration illustrates the concept of air pressure.

Electrochemical Cells - Galvanic (Voltaic) and Electrolytic
Learn about galvanic (voltaic) and electrolytic cells. You'll also get information about anodes and cathodes and direction of electron flow in the two electrochemical cells.

Electronic Configuration of the Elements
This table is a compilation of the electron configurations of the elements up through number 104. Tips for writing out stable configurations and for shorthand notation are included.

Electroplating is the application of electrolytic cells in which a thin layer of metal is deposited onto an electrically conductive surface. Here's a closer look at what electrochemistry is, how it works, and what metals and anodes are used.

Element Atomic Number Quiz
The atomic number of an element is the same as its number of protons. The atomic number determines an element's order in the periodic table. Do you know the numbers of the first few elements? Here's your chance to test yourself, while learning some facts about the elements, too.

Element Color Quiz
Do you know the colors of the chemical elements? Here's a fun multiple choice quiz designed to test your knowledge.

Element List
Here's a list of chemical elements ordered by increasing atomic number. The names and element symbols are provided.

Element Mnemonic Device
Here's a handy mnemonic device to help memorize the symbols and sequence of the first nine elements in the periodic table.

Element Names Spelling Quiz
It's easy to understand how people get confused over the spelling of element names like sulfur, which the IUPAC changed from sulphur (a common spelling still used in some countries). Other element names are just harder to spell. Do you know them all?

Element Photos Needed for the Gallery
This is a list of element photos still needed for the element photo gallery.

Element Photos
You probably know what elemental carbon looks like (think diamond or graphite), but you might not know what indium or cadmium look like. Here's a collection of photographs of the elements to help you out.

Element Picture Quiz
Can you recognize the elements when you see them? Here's a quiz that tests your ability to identify an element based on its appearance.

Element Types - Chemistry of Groups
Learn the locations of element types on the periodic table and get summaries of the defining characteristics of element groups, such as alkaline earths, noble gases, halogens, etc.

Elementary School Physical Science Fair Project Ideas
Trying to find the topic for a science fair project can be almost as challenging as the project itself. Elementary school level projects should be not only informative but quick and fun. Great projects usually answer a question, rather than a general demonstration or display.

Elementary School Science Fair Projects
Find science fair project ideas suitable for the kindergarten through fifth grade level. I've included projects for the preschool level also.

Elements in Fireworks
Learn about the functions of the chemical elements in fireworks.

Elements in the Human Body
Find out what elements are in the human body and what these elements do.

Elements in the Sun
You probably know the sun consists mainly of hydrogen and helium. Can you name the other elements found in our closest star?

Elements Listed by Density
See the order of the chemical elements according to their density (mass per unit volume), from least dense to most dense.

Elements Named for People - Element Eponyms
Alphabetical list of the chemical elements named after people.

Elements Named for Places - Element Toponyms
Alphabetical list of elements in chemistry named for places or element toponyms.

Elephant Toothpaste Chemistry Demonstration
The elephant toothpaste chemistry demonstration produces copious amounts of steaming foam that looks like the toothpaste an elephant might use. Here's how to set up this demonstration and a look at the reactions behind it.

Endothermic and Exothermic Reactions
Learn about endothermic and exothermic chemical reactions and get instructions to perform your own hot and cold chemistry demonstrations.

Endothermic Reaction Demonstration
Here's an endothermic reaction demonstration that is easy to do and cold enough to freeze water.

Endothermic Reaction Examples
Are you looking for examples of endothermic reactions for homework or to set up a demonstration? Here's a list of several heat-absorbing or endothermic chemical reactions and processes.

Environmental Science Fair Projects
Are you interested in doing a science fair project that involves the environment, ecology, pollution, or other environmental issues? Here are some science fair project ideas that involve environmental science.

Ernest Rutherford (1871–1937)
Ernest Rutherford was a British physicist who did research that became the basis for modern nuclear physics. He was awarded the Nobel Prize for Chemistry in 1908.

Experimental Determination of Avogadro's Number
Did you know that Avogadro's number isn't a mathematically derived unit. The number of particles in a mole of a material is determined experimentally. This easy method uses electrochemistry to make the determination.

Factors that Affect Chemical Reaction Rate
Here's a list and description of the major factors that can affect the rate of a chemical reaction. Links for more detailed information are also provided.

Failing Chemistry - What to Do if You Are Failing Chemistry
Are you failing chemistry? Don't panic. Here's a look at what you can do and how you can make the best of the situation and possibly turn it around.

Fake Neon Sign
Do you love the look of neon signs, but want an inexpensive alternative that you can customize to say whatever you want? You can make a fake neon sign using fluorescence to make inexpensive common materials glow.

Fake Snow Instructions
You can make fake snow using a common polymer. The fake snow is non-toxic, feels cool to the touch, and looks similar to the real thing.

Famous Chemists Hangman Game
How well do you know your history? This fun and educational hangman game draws on the names of scientists who made important contributions to the field of chemistry.

Famous Chemists
This is an index of famous chemists and other scientists who made important contributions to the field of chemistry, arranged alphabetically according to the scientist's last name.

Fire & Flames Photo Gallery
Fire and flames are the visible result of combustion. Usually they consist of light and hot gases. Here's a look at some fire, flames, and pyrotechnics.

Fireball Instructions
If you can find a tee shirt and some lighter fluid, you can make small fireballs. These fireballs are re-useable. Theoretically, you can hold them in your hand.

Firecracker How To
Firecrackers are extremely easy and inexpensive to make yourself. Learn how to make homemade firecrackers and how to light them safely.

Firework Periodic Table
Use this special periodic table to find out what elements are found in fireworks and how they are used. Just click on an element to learn more.

Fireworks in a Glass
Fireworks are a beautiful and fun part of many celebrations, but not something you want kids to make themselves. However, even very young explorers can experiment with these safe underwater fireworks.

Fitzroy's Storm Glass
This article introduces a type of weather glass that uses characteristics of precipitants and barometric pressure changes to forecast weather. There are instructions for making a storm glass and links for further meteorology, HMS Beagle, Darwin, and Fitzroy information.

Fizzy Potion Recipe
Make a non-toxic fizzy Mad Scientist potion using ingredients from your kitchen. The potion looks evil, but it is safe enough to drink.

Flame Retardant People
Learn about the health effects of polybrominated diphenyl ether (PBDE), a common flame retardant, and efforts to ban further use of certain forms of the chemical.

Flame Tests
A flame test is an easy experimental technique used to help identify a metal or ionic salt based on its emission spectrum when it is heated in a gas flame. Here's how to perfom a flame test and interpret the results of the test.

Flash Cards - How to Use Flash Cards to Study Chemistry
Flash cards can be a great study aid. You can use them to help memorize facts, lists, and structures as well as to reinforce important concepts. Here's how to prepare and use flash cards to help study chemistry.

Floam Instructions
Make your own version of Floam, a type of slime that contains polystyrene beads so that you can mold it into shapes.

Food Additives
This is a list of common food additives and a description of their uses.

Food and Cooking Chemistry - Science Fair Project Ideas
These are ideas for science fair projects that involve food or cooking chemistry. Links are provided for additional science fair project help and food chemistry information.

Formulas of Common Acids & Bases
Here are the names and formulas of some of the common acids and bases. Learn how to apply prefixes and suffixes to name the acids and bases.

Fountain Firework
Kick the traditional smoke bomb recipe up a notch to make a firework fountain that shoots purple flames with lots of smoke. This is a fun and easy homemade firework project.

Fried Green Egg
Red cabbage juice contains a natural pH indicator that changes color from purple to green under basic (alkaline) conditions. You can use this reaction to make a fried green egg.

Fruit Battery
If you have fruit, a couple of nails, and wire then you can generate electricity to turn on a light bulb. Learn how to make a fruit battery. It's fun, safe, and easy.

Fruit Ripening and Ethylene Experiment
Measure the ripening of fruit from exposure to the plant hormone ethylene by testing starch levels with an iodine solution. This easy experiment can be performed on several types of fruit, such as apples, pears, and bananas.

Functional Groups - Organic Chemistry Essentials
These are the names and structures of important organic functional groups containing nitrogen or oxygen. Learn 'em, live 'em, love 'em!

Gasoline and Octane Ratings
Find out what octane ratings are, how they are calculated, and how to determine the best octane rating to use. There are links to gasoline and alternative fuel sites, as well as to definitions and molecular structures.

GED Chemistry Quiz
Do you know the concepts of general chemistry covered on the science portion of the GED test for a general equivalency diploma? Quiz yourself before taking the big test.

GED Study Guide for Chemisty
One section of the GED or General Education Development Test covers science, including chemistry. This study guide reviews the concepts you can expect to appear on the test.

Gemstone List
This alphabetical list of gemstones includes the mineral names of the gemstones as well as links to photos of the gems.

Gemstone Photo Gallery
See photos of rough and cut gemstones and learn about the chemistry of the minerals.

Geode of Copper Sulfate Crystals
Geodes are rocks that contain crystals. Normally, millions of years are required for flowing water and minerals to deposit crystals, but you can make your own 'geode' in only a few days. Grow blue copper sulfate crystals inside an egg shell to make your own geode.

Getting into Medical School - Clinical Experience
This article explains what clinical experience is, why you need it before applying to medical school, as well as when and how to get it. Links to further information and opportunities are also provided.

Glassware Quiz - Challenging
This multiple choice quiz tests your ability to recognize different pieces of glassware that you would find in a chemistry lab.

Glassware Quiz
Can you recognize basic pieces of laboratory glassware when you see them? Here's a quiz that tests your ability to identify glassware based on its picture. These are standard items found in a chemistry lab, not tricky or specialized pieces of glassware.

Glenn Theodore Seaborg (1912 - 1999)
Glenn Seaborg is known for his work with transuranic elements. Here is a brief biography for this influential scientist.

Glow in the Dark Crystal Geode
It's very easy to make a glow in the dark crystal geode. The rock is a natural mineral (eggshell). You can use one of several common household chemicals to grow the crystals. The glow comes from phosphorescent paint, which you can get from a craft store.

Glow in the Dark Mountain Dew
All it takes is a few easily-obtained materials to turn a bottle of Mountain Dew into a glow in the dark bottle of Mountain Dew.

Glow in the Dark Photo Gallery
Here's a collection of photos of materials that glow in the dark. Why do objects glow? It could be due to radioactive decay or a chemiluminescent reaction or any of a variety of other types of luminescence.

Glow in the Dark Slime
What is better than regular slime? Slime that glows in the dark, of course! This is an easy and fun project that is suitable for kids.

Glow-in-the-Dark Crystal Snowflake
Learn how to make a glow-in-the-dark crystal snowflake or other glowing holiday ornament. This is a safe and easy project that's great for kids and kids-at-heart. The crystal decorations are light-weight and inexpensive to make.

Glowing Bubbles
Bubbles are already awesome, but glowing bubbles are even better. It is easy and safe to make bubbles glow, plus it doesn't require any hard-to-find materials. Here is what you do.

Glowing Hand of Doom Punch
Glowing Hand of Doom punch is a great punch for Halloween parties or mad scientist parties. Here's how to make a glowing hand rise from the punch, which is bubbling and producing fog.

Glowing Ice Sphere
There are a few different ways you can make a non-toxic glowing ice sphere. You can even make a glowing crystal ball that you can float in a bowl of punch to drink.

Glowing Jell-O Recipe
It's incredibly easy to make Jell-O or other gelatin glow under a black light. Here's what you do.

Glowing Water
It's really easy to make glowing water that you can use as glowing water or as a glowing ingredient in other water-based projects.

Glycolysis is the name given to the series of biochemical reactions in which glucose is converted into pyruvate. This important part of carbohydrate catabolism takes place in the cytoplasm of cells. Several reactions take place, with products that are vital to the functioning of the cell.

Gold Alloys
None of the gold used in jewelry is pure gold. Some gold isn't even 'gold'-colored (e.g., white gold). The different colors are due to the presence of other metals alloyed with the gold. This table gives common compositions of the different colors of gold.

Gold and Silver Pennies
Take copper pennies and turn then silver, then make them gold. This is an easy chemistry project that uses common laboratory chemicals.

Goo Recipe
Make squishy non-toxic goo that hardens in your hands when you squeeze it, but flows like a liquid when you pour it.

Goo Slime Recipe #2
Goo slime is a type of slime that flows when you pour it, but hardens when you squeeze it. Goo is non-toxic and easy to make using two common household ingredients.

Greek Alphabet
The Greek Alphabet is used extensively in science and mathematics to represent variables and symbols. This table lists all twenty four Greek letters in upper and lower case. Learning the names of these letters is easy and you may be surprised to find you already know them.

Green Fire Halloween Jack-o-Lantern
A Halloween jack-o-lantern filled with green fire is much more impressive than one lit with the usual candle. Here's how to produce this easy effect yourself.

Green Fire Instructions
It's easy to make brilliant green fire. This cool chemistry project only takes two household chemicals.

Green Sand Beach
Hawaii's Green Sand Beach is an unforgettable destination. Learn why the sand is green and how to get to the beach.

Groups of Elements - Periodic Table
Elements can be categorized according to their similar properties. Here's a periodic table that organizes the elements according to groups. Click an element symbol and learn about the group to which it belongs.

Grow Red Potassium Ferricyanide Crystals
These are instructions for growing easy red monoclinic crystals. Don't let the 'cyanide' part of the chemical name put you off -- these crystals aren't edible, but neither are they more toxic than most other compounds.

Grow Sugar Crystals - Make Your Own Rock Candy
Sugar crystals are also known as rock candy since the crystallized sucrose resembles rock crystals and because you can eat your finished product. You can grow clear sugar crystals with sugar and water or you can add food coloring to get colored crystals. It's simple, safe, and fun.

Growing Crystals - Science Fair Project Ideas
Are you looking for a fun science fair project idea? Here are some ways you can turn crystal growing into a research project. There are links to instructions for growing different types of crystals and for designing a great science fair project, too.

Growing Crystals - Troubleshooting Common Problems
Are you having trouble growing crystals? Before you throw out your solution, read this list of common problems and fixes.

Hair Color Chemistry
Over 75% of women and a growing percentage of men color their hair. Learn about natural haircolor and find out what happens when you bleach hair or use temporary or permanent haircolor.

Halloween Reaction or Old Nassau Reaction
The Old Nassau or Halloween reaction is a clock reaction in which the color of a chemical solution changes from orange to black. Here's how you can do this reaction as a chemistry demonstration.

Hawaii Chemistry
Take a look at the Big Island of Hawaii from a chemistry perspective.

Hazard Symbol Quiz
This fun multiple choice quiz tests your recognition of lab safety signs and symbols. If you fail this quiz you might want to avoid the chem lab until after you have reviewed the meanings of the signs.

Heats of Formation - Anions & Cations
This is a table of molar heats of formation for common anions and cations in aqueous solution.

Henderson Hasselbalch Equation and Example
You can calculate the pH of a buffer solution or the concentration of the acid and base using the Henderson Hasselbalch equation. Here's a look at the Henderson Hasselbalch equation and a worked example that explains how to apply the equation.

Hiddenite Gemes - Emerald Hollow Mine
The Emerald Hollow Mine in Hiddenite, NC is the only emerald mine in the United States open to the public for prospecting. I went to North Carolina to check the mine out for myself. Can you find emeralds? Yes! And rubies, sapphires, amethyst, citrine, the rare gemstone hiddenite, and much more.

High School Courses Needed for College Chemistry Major
Are you a middle school or high school student contemplating a college major in chemistry? Here's a look at some of the courses that can help you with your goal!

High School Science Fair Projects
Get ideas for great high school science projects. These are projects targeted from the 9-12 grade educational level.

History of Fireworks
Fireworks are a traditional part of most Independence Day and New Year's celebrations. Learn about the invention of fireworks and the history behind how fireworks are used.

History of Matches
Fire may have been around since the dawn of civilization, but matches are a fairly recent invention. Learn about the somewhat gruesome history of the chemical or friction match and how antimony and phosphorus are used to start fire.

Holiday Science Projects
Are you looking for fun and educational science projects that you can do for the winter holidays? These seasonal activities and experiments will entertain you, plus you may learn something too.

Hollow Penny Project
This is an easy chemistry project that uses common materials. You take a post-1982 penny, score the copper surface to expose the zinc interior, react the zinc with acid, and are left with a hollow copper penny.

Home and Garden pH Indicators
Here's a list of common household substances and garden plants that can be used as pH indicators. Many of the active molecules, expected color changes, and pH ranges are listed.

Home Chemistry Supplies List
Put together a home chemistry kit with common household chemicals and a few simple materials.

Honeycomb Candy Recipe
Honeycomb candy is an easy-to-make candy that has an interesting texture caused by carbon dioxide bubbles getting trapped within the candy.

Hot Ice or Sodium Acetate
Sodium acetate or hot ice is an amazing chemical you can prepare yourself from baking soda and vinegar. You can cool a solution of sodium acetate below its melting point and then cause the liquid to crystallize. The crystallization is an exothermic process, so the resulting ice is hot. Solidification occurs so quickly you can form sculptures as you pour the hot ice.

Household Product Recipes
You can use home chemistry to make many of the everyday household products that you use. Making these products yourself can save you money and allow you to customize formulations to avoid toxic or irritating chemicals.

Household Product Testing - Science Fair Project Ideas
Science doesn't have to be expensive and it doesn't require specialized lab equipment! These are ideas for science fair projects that involve testing or comparing common household products.

How Are Elements Named?
Have you ever wondered how the elements are named or why some elements have more than one name? Here's the answer to your question.

How Are New Elements Discovered?
Find out if there are any elements left to be discovered and how they would be found.

How Do Chemical Weapons Smell?
Do you think chemical weapons smell terrible? You might be surprised to learn many are odorless or smell pleasant.

How Do Detergents Clean?
Learn about the chemistry behind the cleaning power of detergents.

How Do Disposable Diapers Work? Why Do They Leak?
Learn about the polymer in disposable diapers, sodium polyacrylate. Find out how the polymer absorbs water and why diapers leak.

How Do I Substitute Between Baking Powder and Baking Soda?
Baking powder and baking soda both are leavening agents, which means they help baked goods to rise. They are not the same chemical, but you can substitute one for another in recipes. Here's how.

How Do Lightsticks Work?
Find out how lightsticks or glowsticks work. Learn about the chemistry behind the process and get on-line purchase information. This article also explains how to make glow sticks last longer or become brighter!

How Do Mood Rings Work?
Mood rings have a stone that is supposed to change color to show your emotions. Do they work? If so, do you know how? Here's your chance to find out.

How Do Pencil Erasers Work?
Learn about the different materials used as pencil erasers and how they work.

How Do Pop Rocks Candy Work?
Find out how pop rocks candy works and whether or not it's true your stomach will explode if you wash down pop rocks with soda.

How Do Pregnancy Tests Work?
Learn how blood tests and home pregnancy urine tests work, how early they can be used, and some reasons for false positive and negative test results.

How Do Safety Matches Work?
Learn about how safety matches work and why they are considered 'safe'.

How Do Smoke Detectors Work?
Find out how ionization and photoelectric smoke detectors work. Then determine which type is better for your needs. Links are supplied to give you more information about fire safety, tips for installing a smoke detector, and answers to common smoke detector questions.

How Do Sparklers Work?
This type of firework produces a cascade of fiery sparks. Learn about the chemistry behind the sparks or find formulae to make your own!

How Do Sunless Tanning Products Work?
This article discusses bronzers, self-tanning lotions and sprays, tanning accelerators, and pills. Learn how these products work and find out why tans fade.

How Do Trick Birthday Candles Work?
You blow them out, but these candles re-light themselves. Magic? No, it's simple chemistry!

How Does Borax Clean?
Borax is used as a multipurpose cleaner and bleach. How does it work? Learn how the chemistry of borax relates to its cleaning power. These same properties are also associated with certain health hazards.

How Does Soap Clean?
You may use it every day, but do you know how it works? Learn about emulsions, micelles, and soap scum! Then check out links to sites about bubbles, soapmaking, and the regulation of soap chemistry.

How Does Stainless Steel Remove Odors?
Have you heard about the kitchen tip in which you rub your fingers across the blade of a stainless steel knife to remove odors from onions, garlic, and fish? You have now! Learn about the chemistry behind this interesting bit of cooking magic.

How Fireworks Work
Firecrackers, sparklers, and aerial fireworks are all examples of fireworks. Here's a look at the different types of fireworks and an explanation of how they work.

How Sunscreen Works
Find out how sunscreen works, what an SPF rating means, the difference between sunscreen and sunblock, and how to protect yourself from both UV-A and UV-B radiation.

How to Clean Laboratory Glassware
Cleaning laboratory glassware isn't as simple as washing the dishes. Here's how to wash your glassware so that you won't ruin your chemical solution, laboratory experiment, or the glass.

How To Color Fire
Have you ever wanted to color fire? Here are simple, nontechnical instructions for making your own colored flames. Add extra interest to your fireplace or campfire!

How to Fail a Chemistry Class
Avoid these mistakes to help ensure success in your chemistry class.

How to Grow Great Crystals
Do you want to grow crystals, but you aren't sure where to start or what to do to make sure your crystals turn out well? Here's some basic information on crystal growing. I've provided links to recipes so you can start growing crystals. These instructions are general, so if your recipe calls for something special (like no vibrations or dark), be...

How to Grow Table Salt or Sodium Chloride Crystals
It's easy to grow your own table salt or sodium chloride crystals. All it takes is salt and boiling water. One method even yields crystals within a few hours. Here's what you need to know.

How to Make Aspirin - Acetylsalicylic Acid
Learn how to synthesize aspirin, acetylsalicylic acid, from salicyclic acid. Get information about the history of aspirin, the effects of salicylates, and see the structures of the reactants.

How to Make Ice Cream in a Baggie
Make a tasty treat and learn about freezing point depression, too! All you need are some basic ingredients and two ziploc baggies. It's easy, fun, and educational.

How to Make Liquid Magnets - Synthesize Ferrofluid
Make your own ferrofluid, or liquid magnet, which can be used with a magnet to change the liquid's density and to form spikes and other amazing shapes.

How to Make Moonshine
Moonshine is a liquor made from fermented corn. Learn about distillation, condensation, and how this alcoholic beverage is made.

How to Make Red Cabbage pH Indicator
Make your own pH indicator solution! Red cabbage juice indicator is easy to make, exhibits a wide range of colors, and can be used to make your own pH paper strips.

How to Make Snow
If you want snow, but Mother Nature won't cooperate, you can take matters into your own hands and make snow yourself! This is the homemade version of real water ice snow, just like the snow that falls from the sky except without the need for clouds.

How to Perform a Recrystallization
Recrystallization is a laboratory technique used to purify a sample based on the different solubilites of its components. Learn how to perform a recrystallization and get tips on how to avoid common problems and improve your product yield.

How to Prepare for the MCAT
The Medical College Admission Test is a required part of the application to US medical schools and certain other professional schools. The exam covers general chemistry, organic chemistry, biology, physics, verbal reasoning, and writing. Here are tips to help you prepare for the big test day!

How to Prepare Gases
Here are simple instructions for preparing common gases from ordinary chemicals. The gases include carbon dioxide, oxygen, nitrogen, methane, nitrous oxide, chlorine, and several others.

How to Read a Meniscus
The meniscus is the curve seen at the top of a liquid in response to its container. When you read a scale on the side of a container with a meniscus, such as a graduated cylinder or volumetric flask, it's important that the measurement accounts for the meniscus. Here's how to read a meniscus.

How to Remove Ball Point Pen Ink
Ball point pen ink is not a something that you can usually remove with simple soap and water, but there is an easy and inexpensive way to remove pen ink from surfaces or clothing.

How To Remove Fluoride from Drinking Water
This is a list of methods that can be used to remove fluoride from drinking water. There's also a list of methods that do not remove fluoride and suggestions for ways to minimize fluoride exposure. References for the fluoridation controversy are included.

How to Remove Rust Stains
Rust stains can be a challenge to remove because the stain consists of tiny iron oxide particles, plus some treatments actually set the stain rather than remove it. Use a little chemistry know-how to successfully remove a rust stain.

How to Take a Test
How you take a test is at least as important as your preparation for it. These tips can help you make the grade.

How to Write a Bibliography for a Science Fair Project
Learn how to cite your sources for a science fair project. See examples for books, online references, and conversations.

How to Write a Lab Report
Lab reports are an essential part of all laboratory courses and usually a significant part of your grade. If your instructor gives you an outline for how to write a lab report, use that. Here's a format for a lab report you can use if you aren't sure what to write or need an explanation of what to include in the different parts of the report.

HTML Codes - Greek Letters
Here is a table of HTML codes for Greek letters used when creating web content for science and mathematics.

HTML Codes - Mathematical Symbols
A table of commonly used mathematical symbols used in creating html web content for science and mathematics.

HTML Codes - Variables and Scientific Symbols
Here is a table of commonly used symbols used in creating html web content for science and mathematics.

Ideal Gas Example Problem - Constant Volume
Here is an example of an ideal gas problem where the volume of the gas is held constant.

Ideal Gas Quiz
Do you understand the ideal gas laws? Here's a ten question multiple choice quiz you can take to test your knowledge.

Identify an Unknown - Experiment with Chemical Reactions
Use this chemistry lesson plan to help students use the scientific method to design experiments to identify the components of an unknown mixture.

If Civilization Ended Today, Could I Still Make Beer?
If civilization ended right now, could I still make beer? Learn about how beer is brewed and what is required to make this popular alcoholic beverage.

If I Leave My Goldfish in the Dark, Will it Turn White?
Learn about pigment biochemistry and find out whether your goldfish will turn white if you leave it in the dark long enough.

Importance of Chemistry
What is the importance of chemistry? Why would you want to learn about chemistry? Chemistry is the study of matter and its interactions with other matter and energy. Here's a look at the importance of chemistry and why you should study it.

Incompatible Chemical Mixtures
Here's a list of chemicals that you don't want to accidentally mix, together with brief statements about the expected reactions. Use this information to avoid accidents and ensure safe storage and handling of potentially dangerous substances, both at work and at home.

Insta-Snow Review
Insta-Snow is white like real snow, wet, and flakey, but it's made from a polymer gel rather than water and it doesn't melt. Is it fun? Is it safe? Is is cool? Here's what I thought of Insta-Snow.

Instant Fire Chemistry Demonstration
Learn how to perform the instant fire chemistry demonstration in which potassium chlorate and sugar are reacted to produce an incredible purple flame and a lot of smoke.

Interpreting Statements in Scientific Papers
What does it mean when a scientists writes, "it can be shown" or "a trend is obvious"? Here are translations for these and other common phrases used in research papers.

Interview: Bill Carroll, President - The American Chemical Society - ...
ACS President Bill Carroll chats about his interest in chemistry, Chemistry Week 2005, and how chemistry impacts our daily lives in this exclusive interview with Stephanie Holbrook.

Introduction to Chemistry Quiz
This multiple choice quiz tests your understanding of introductory chemistry concepts. It covers matter, chemical and physical changes, energy, endothermic and exothermic reactions, measurements, significant figures, and scientific notation.

Introduction to Molecular Geometry
Molecular geometry is the three-dimensional arrangement of atoms within a molecule. Here's an introduction to molecular geometry with instructions for how to predict configuration and a table of VSEPR geometries.

Introduction to Spectroscopy
Learn what spectroscopy and spectra are, how spectroscopy works, and what it is used for. This article includes a list of several different spectroscopies, with brief descriptions of their characteristics.

Introduction to the Periodic Table
Learn how the periodic table of the elements is structured. Get basic history about its development and learn how periods and groups relate to electrons and atomic mass.

Invisible Ink Revealed - How to Read Invisible Ink Messages
It's easy to write a message using invisible ink, but it's a little trickier to read the message. Here are tips for revealing an invisible ink secret message.

Invisible Inks
Make your own invisible ink so you can write and reveal secret messages. Get information about inks that are activated by heat, chemical reactions, and ultraviolet light.

Ionic & Covalent Bonds
Learn to distinguish between ionic and covalent bonds, and determine whether a bond will be polar or nonpolar.

Ions, Isotopes, Atoms Quiz
If you're given the nuclear symbol for an element, can you identify how many protons and neutrons it has? If you see an ion symbol, do you know how many electrons are present? Here's your chance to test yourself.

Irving Langmuir (1881 - 1957)
Irving Langmuir is known for his work on thin film and surface chemistry. He was a prolific innovator for General Electric and produced over 60 patents for them.

Is It Safe to Use Kitchen Glassware for Chemistry?
Is it safe to use your kitchen glassware and utensils for chemistry experiments? Here's a look at some of the risks involved in using your dishes for chemistry.

Is There Really a Chemistry of Love?
Sweaty palms and a pounding heart don't just happen! It takes complex biochemistry to give you the symptoms of being in love. And lust. And security. Chemistry may even play a role in falling out-of-love. Get some of the details here, with links for further study.

Ivory Soap Microwave Trick
Microwave a bar of Ivory soap and watch it expand to over six times its original size. The foam trick is good clean fun, plus it can be used to demonstrate Charles' Law, physical change, and foam formation.

Jacobson's Organ and the Sixth Sense
In many animals Jacobson's organ is responsible for sensitive chemical detection and pheromone communication between members of the same species. Is Jacobson's organ responsible for the sixth sense in humans?

Javascript Periodic Table of the Elements
This is an interactive javascript periodic table of the elements. Click on an symbol on the periodic table to get facts about the element.

Joseph Louis Gay-Lussac (1778 - 1850)
Gay-Lussac was a French chemist and physicist known best for his work with gases and the composition of the Earth's atmosphere. He is credited with the discovery of boron. His work with measuring alcohol and water gave us the measure 'degrees Gay Lussac', which is still used in many countries as a measure of alcohol content in drinks.

Ketchup and Baking Soda Volcano
The acetic acid in ketchup reacts with baking soda to produce an extra-special type of lava for a chemical volcano. This is a non-toxic volcano recipe that is sure to please!

Kid-Friendly Elephant Toothpaste Demo
The elephant toothpaste demo produces a growing column of foam that looks like what you would get if an elephant squashed a giant tube of toothpaste. Here's a kid-friendly version of this classic chemistry demonstration.

Lab Equipment & Instruments
Find images of laboratory equipment and instruments, including glassware and antique items.

Laboratory Safety Quiz
Are you a safe scientist or a menace to yourself and others in the chemistry lab? Here's a ten question quiz you can take to test yourself. It's sarcastic and maybe even a little mean, but... some accidents just shouldn't happen.

Lanthanides and Actinides - The Rare Earths
Learn about the properties of the rare earth metals. This 3-part article includes an overview of the rare earths and separate sections for the lanthanide series and actinide series.

Laundry Detergent Glowing Skull
If you have laundry detergent, you can make a glow-in-the dark skull that you can put on your sidewalk or window that will be invisible during the day but will glow at night. Here's how you do it.

Laundry Detergent Recipe
It's easy to make your own laundry detergent, plus the cost of using it is about a tenth the price of using store-bought laundry detergent. Here's how you make this cleaner yourself.

Lava Lamp - Make a Lava Lamp
Lava lamps are interesting and cool. Have you ever wanted to make your own lava lamp? Lava lamps that you buy use high heat and toxic chemicals, but you can make a lava lamp at home using safe kitchen ingredients. Here's how.

Laws of Chemistry
Here's a reference page that describes the major laws of chemistry.

Laws of Thermochemistry
Certain rules or laws apply to thermochemical equations and enthalpy. These are explanations and examples of these laws, including Hess's Law.

Lemon Fizz Science Project
The lemon fizz project is a fun bubbly science project using kitchen ingredients that’s ideal for kids to try.

Lewis Structures or Electron Dot Structures
Learn about Lewis structures, also called electron dot structures and get step-by-step help drawing them.

Lichtenberg Figures
Lichtenberg figures essentially capture the image of lightning. Here's how you can make your own Lichtenberg figure from common materials.

Light Stick Colors
This article lists some of the fluorophors that are used to give light sticks different colors. The oxalate chemiluminescent reactions are introduced.

Liquid Nitrogen Facts
Liquid nitrogen is nitrogen that is cold enough to exist in liquid form. It is used for many cooling and cryogenic applications. Here are some liquid nitrogen facts and information about handling liquid nitrogen safely.

Liquid Nitrogen Ice Cream
Make liquid nitrogen ice cream as a cool cryogenics or phase change demonstration or for a quick and tasty treat.

Luminol Chemiluminescence Test for Blood
You can use the luminol chemiluminescence reaction as a quick and easy forensic test for blood. Here's a look at what you need to perform the test, how to do it, and an explanation of how the luminol test works.

Mad Cow Disease - What You Need to Know
When it comes to Mad Cow Disease, it's difficult to separate fact from fiction and hard data from supposition. Part of the problem is political and economical, but a lot of it is based in biochemistry. Here's a summary of what you need to know.

Mad Scientist Party
A mad scientist party is a fun and educational party theme, ideal for birthdays and Halloween. Get ideas for invitations, decorations, costumes, food and drink, cakes, mad scientist experiments and games, as well as party favors for guests to take home.

Magic Colored Milk Science Project
If you add food coloring to milk, not a whole lot happens, but it only takes one simple ingredient to turn the milk into a spinning color wheel. Here is what you do.

Magic Crystal Christmas Tree
A magic crystal Christmas tree is an easy crystal project you can do for the holidays.

Magic Rocks - Review
Magic Rocks are a classic instant crystal growing kit. You pour a magic solution over magic rocks and a fanciful crystal garden starts growing as you watch. Here's my review of the Magic Rocks kit.

Magnetism Science Fair Projects
Do you like magnets? Science fair projects can examine magnetism or electromagnets. Here are some magnetism science fair project ideas.

Make a Bouncing Polymer Ball
Use chemistry to make a bouncing polymer ball, then alter the procedure to see the effect the changes have on the charactertistics of the bouncing ball.

Make a Mixture and a Compound from Iron and Sulfur
Do you know the difference between a mixture and a compound? Combine iron and sulfur to make a mixture and then react them to form a chemical compound.

Make Frozen Bubbles
Use dry ice to freeze bubbles solid so that you can pick them up and examine them closely. You can use this project to demonstrate several scientific principles, such as density, interference, semipermeability, and diffusion.

Make Your Own Magic Rocks - Chemical Garden
Learn about the chemistry behind magic rocks and make your own chemical crystal garden.

Marie Sklodowska Curie (1867–1934)
Marie Sklodowska Curie was a Polish-born French scientist. She won the Nobel Prize twice and was famous for her work on radioactivity.

Marijuana Facts
Learn what marijuana and THC are, why people use marijuana, where it comes from, and what risks are associated with using marijuana.

Match Rockets
A match rocket is an extremely simple rocket to construct and launch. The match rocket illustrates many rocketry principles, including basic jet propulsion and Newton's laws of motion. Match rockets fly several meters, in a burst of heat and flame.

Materials Science Fair Projects
Materials science involves physical science and engineering. Science fair projects can invent new materials, improve existing materials, test the properties of materials, or compare the suitability of different materials for a specific purpose. Here's a look at some science fair project ideas in this field of research.

MCAT Study Guides
Many medical schools require applicants to submit MCAT scores. The MCAT, or Medical College Admission Test, consists of sections on Verbal Reasoning, Physical Sciences, Writing Sample, and Biological Sciences. The MCAT can be intimidating, so you might consider purchasing a study guide or review text.

Measurement of Heat Flow - Coffee Cup & Bomb Calorimeters
A calorimeter is a device used to measure the quantity of heat flow in a chemical reaction. Learn about two of the most common types of calorimeters, the coffee cup calorimeter and the bomb calorimeter, and find out how to use them to calculate heat flow and enthalpy change.

Measurements & Conversions Quiz
Take a multiple choice quiz to test your comprehension of units, conversions, and significant figures.

Medical School Interviews
Knowing what to expect in a medical school interview is a key to success. This article focuses on dressing for success and provides valuable tips for after the interview. Links to interview databases and common interview questions/answers are included.

Melting Snow & Ice with Salt
You know salt is sprinkled on roads and sidewalks to melt ice and prevent it from refreezing, but do you know how it works? Learn about freezing point depression and colligative properties and find out about the pros and cons of several de-icers.

Mentos & Diet Soda Chemical Volcano
Candies and diet soda together can make a chemical 'volcano' with an eruption several feet high. If the normal baking soda volcano is too tame for you, give this project a try.

Metal Jewelry Stamps & Marks
Jewelry made from precious metals often is stamped with a mark to indicate the chemical composition of the metal. These stamps or engravings are called quality marks. Here's a look at what different quality marks signify. Gold, silver, vermeil, platinum, and palladium are included.

Metric Prefixes Quiz
How well do you know your metric prefixes? Quiz yourself with this ten question multiple choice self-test.

Metric to Metric Conversions - Unit Cancelling Method
Here is a step by step example of a conversion between metric units. This illustrates how to cancel units to convert measurement units.

Metric Unit Prefixes
Metric units of measurement are all based on units of ten. Here is a list of the most common metric unit prefixes.

Metric Units - Base Units
The metric system or SI (from Le Système International d'Unités.) is based on seven base units. These units describe the basic properties on which all other measurements are based.

Metric Units - Derived Metric Units
Many metric units used in science have specialized names for the values they represent. They are considered derived units and can still be reduced to factors of the seven base units. This table lists many of these units and their corresponding base unit values.

Middle School Science Fair Projects
Find ideas for middle school science fair projects. These are projects suitable for the 6-8 grade level.

Mohs Scale of Hardness
The Mohs Scale of Hardness measures how well a substance resists scratching by another material. You can use this scale to test the hardness of rocks, minerals, and crystals, to help identify them.

Molarity Example Problem
Here is an example of calculating concentration or molarity of a solution.

Molecule Hangman Game
This hangman game draws on names of molecules from the Molecular Structures Library. Possible chemicals include amino acids, nucleic acids, chemical warfare agents, pesticides, molecules found in food, and other names from the libary list.

Molecules and Moles
Learn how molecules, moles, and Avogadro's number relate to each other. This is a good introduction to the study of compounds and stoichiometry.

Molecules with Strange or Silly Names
Molecules don't always have long alphabet-soup names. Chemists have a sense of humor. Sometimes molecules have amusing names. Here are some examples of molecules with funny, strange, or silly names.

MRI Reaction with Tattoos
Is a burning reaction between a tattoo and magnetic resonance imaging (an MRI) based in fact or is it an urban legend? Here's the answer!

Natural Easter Egg Dyes
These are easy instructions for making your own natural Easter egg dyes, using fruits, vegetables, and spices.

Natural Insect Repellent Recipe
You can make natural insect repellent yourself. The insect repellent is safe and effective, plus it costs much less to make it than to buy it.

Natural Mosquito Repellents
Looking for a natural alternative to synthetic chemical mosquito repellents? Find out which natural substances repel mosquitoes, how to avoid attracting them, and how to maximize the effectiveness of your repellent.

Nernst Equation
The Nernst equation is used to calculate the voltage of an electrochemical cell or to find the concentration of one of the components of the cell. Here is a look at the Nernst equation and an example of how to apply it to solve a problem.

Nitrogen Cycle
Learn about the processes involved in the nitrogen cycle, the biochemical cycle that describes the transformations of nitrogen as it goes through nature.

Nitrogen Triiodide Chemistry Demonstration
Learn how to perform the nitrogen triiodide chemistry demonstration, a spectacular touch-sensitive decomposition that produces a cloud of purple smoke and a loud 'snap'.

Nuclear Reactions - Mass - Energy Relations
Learn how to calculate the energy change in a nuclear reaction, such as radioactive decay.

Oobleck Recipe
Learn how to make Oobleck, a type of slime that has properties of both liquids and solids.

Orange Potassium Dichromate Crystals
Do you want crystals that are naturally bright and colorful? Grow orange crystals of potassium dichromate.

Paramagnetism and Diamagnetism Worked Problem
Here is a worked example problem showing how to tell whether an element is paramagnetic or diamagnetic based on its electron configuration.

Patio Table Crystals
Turn the surface of your glass patio table into a safe place for kids to explore crystals. Here's an easy crystal project you can do on any warm, sunny day using ingredients from your kitchen.

Pepper and Water Science Magic Trick
The pepper and water science trick is one of the easiest magic tricks you can perform. Here's how to do the trick and an explanation of how it works.

Percent Composition by Mass
Here is an example of calculating concentration using percent composition by mass of a solution.

Perform the Mohs Test
The Mohs test is one way to determine the hardness of a rock or mineral. You can use the Mohs hardness to help identify an unknown specimen. Here's how you can do the test yourself.

Perfume Recipe
Perfume is a classic gift, but it's even better if it is a scent that you made yourself, especially if you package it in a beautiful bottle. Perfume you make yourself is free from synthetic chemicals and is fully customized to your personal taste. Here's how to make your own perfume.

Perimeter and Surface Area Formulas
Perimeter and surface area formulas are part of the math used in common science calculations. You While it's a good idea to memorize these formulas, here is a list of perimeter, circumference and surface area formulas to use as a handy reference.

Periodic Properties of the Elements
The properties of the elements exhibit trends. These trends explain the periodicity observed in atomic radius, ionization energy, electron affinity, and electronegativity. Learn how to use the periodic table to predict the trends in elemental properties.

Periodic Table of the Elements for Kids
This table was made with kids and homework in mind. It includes element groups and periods, element symbols, atomic numbers, atomic weights, and links to detailed facts for each element.

Periodic Table Study Guide
Learn about the periodic table of the elements. Find out about the history of the periodic table, how the elements are organized, and how to use the periodic table to predict the behavior of unfamiliar elements.

pH of Common Chemicals
Here's a table of the pH of several common chemicals. You can use the list to set up color ranges for pH indicators or simply to learn more about acids and bases.

Phases & Phase Changes Quiz
Take this multiple choice quiz to test your understanding of the states of matter.

Photosynthesis Basics - Study Guide
Photosynthesis is the name for the set of chemical reactions used by plants and other organisms to make food from sunlight, carbon dioxide, and water. Here's a look at the process and study questions to help make sure you understand the key concepts.

Physical Constants, Prefixes, and Conversion Factors
This is a set of tables with some useful physical constants, conversion factors, and unit prefixes. They are used in many calculations in chemistry, as well as in physics and other sciences.

Pictures of Famous Chemists
These are images of famous chemists or other scientists who made significant contributions to the field of chemistry.

Pictures of Laureates for the Nobel Prize in Chemistry
This is a collection of photographs of the winner for the Nobel Prize in Chemistry.

Pictures of Women in Chemistry
See photos of women who made contributions to the field of chemistry.

Poinsettia pH Paper
You can make pH indicator from poinsettia flowers, then use the indicator to make your own pH paper test strips.

Potato Clock - Make a Potato Battery to Power an LED Clock
A potato can function as an electrochemical cell or battery. It's fun to use a potato to power an LED clock.

Printable Chemistry Worksheets
This is a collection of chemistry worksheets in pdf format. The answers to the questions are available on separate worksheets so you can fill them out and then check your work.

Printable Periodic Table of the Elements
Download or print these periodic tables to help work chemistry problems or to predict properties of the elements.

Protein and Polypeptide Structure
This article describes the four levels of protein and polypeptide structure, with examples and links for additional reading.

Qualitative Analysis - Bead Tests
The borax, microcosmic salt, or sodium carbonate bead test may be used to help identify unknown metals. Learn how to perform and interpret the results of this handy analytical test.

Qualitative Analysis - Flame Tests
The flame test is a quick low-tech method of identifying an element by the color of light it yields in a flame. Learn how to perform this test and to interpret the results.

Quick Crystal Growing Projects
Grow crystals quickly and easily with these top crystal growing projects.

Quick Sheet Crystals
If you don't have the time or patience to grow crystals over hours, days, or longer, try growing these sheet crystals. You'll get results in seconds!

Radioactive-Looking Slime
The slime you might find in a real Mad Scientist's lab would probably be the result of some horrible genetic mutation. You can make slime that looks radioactive and toxic, yet is actually easy to make and safe. Here's how you do it.

Radioactivity & Nuclear Reactions Quiz
This ten question multiple choice quiz tests your understanding of nucleonics. It covers alpha, beta, and gamma radiation, radioactive dating, fission and fusion.

Rainbow in a Glass Density Demonstration
Make a rainbow in a glass using colored sugar solutions with different densities. This project is very easy and safe enough to drink.

Rate of Radioactive Decay
Work through an example chemistry problem on the rate of radioactive decay, a type of first order rate reaction.

Re-Use the Turkey Thermometer
You can re-use the pop-up thermometer that comes with a frozen turkey. Here are easy instructions to re-set the thermometer, which you can then you for another turkey or for other types of poultry.

Reactions in Water or Aqueous Solution
Let's review some important types of reactions that occur in aqueous solution and take a look at the rules that are used when writing balanced equations for water reactions.

Recycled Paper
Make beautiful paper from recycled scraps of just about any paper project you can find. Learn how to add decorative items to your paper and prepare it for writing or stamping. This is a fun craft that teaches about recycling while making a useful handmade product.

Red Cabbage pH Paper
Learn how to make your own pH indicator test strips using red cabbage. This is a fun, safe, and easy chemistry project that you can do at home.

Red Fire Instructions
Red fire is easy to produce. This is a classic color for sparklers and fireworks as well as holiday parties. It would also be a cheery coloration for a campfire or fireplace.

Red Mercury - Thoughts and Speculation
William Yerkes offers insight into red mercury, a material purportedly implicated in fusion-device research.

Reference Books Every Chemist Should Own
There are some reference books I reach for again and again. If your personal library doesn't include these books, maybe it's time to add them.

Review of 'Adventures in the Atomic Age'
Nobel laureate Glenn Seaborg's autobiography relates the development of nuclear science and policy and science education. Seaborg takes the reader through his life, from his beginnings in a Michigan company town, to Berkeley and research on transuranium elements and university administration, to Chicago and the Manhattan Project, to Washington and nuclear policy.

Review Returned Tests
Learn why you should review a returned chemistry test and how to do it to gain the most benefit from the exam.

Ricin and RCA - Castor Bean Toxins
Learn about ricin and RCA, the two potent toxins from the castor bean plant. Information is provided about the action, symptoms, and treatment of ricin and RCA poisoning.

Robert Boyle (1627 - 1691)
Robert Boyle was an Irish-born scientist best known for Boyle's Law of Ideal Gases. He also was a founding fellow of the Royal Society of London and an early supporter of the atomic nature of matter.

Rock & Mineral Chemistry Quiz
Do you know about the chemistry of rocks and minerals? Here's a ten question quiz you can take to test your knowledge.

Rock Candy Instructions
Rock candy is candy made by crystallizing sugar. You can grow sugar crystals yourself, plus add color and flavor to make rock candy that you can eat.

Rock Tumbler Instructions
Here are instructions for tumbling rocks using a rotary drum tumbler and a vibratory tumbler, as well as instructions for polishing jewelry in a rock tumbler. Helpful tips are included for improving the polish and troubleshooting problems.

Rubber Egg & Chicken Bones
You can make a hard boiled egg bounce like a rubber ball and cause chicken bones to become soft and rubbery. All you need is a common kitchen ingredient.

Rules for Assigning Oxidation Numbers
Learn how to assign oxidation numbers to keep track of the distribution of electrons during a chemical reaction.

Safe Smoke Bomb Instructions
A classic smoke bomb is easy to make and safe to use, but you can make the project even safer if you don't heat the ingredients. Here's what you do.

Salt & Sugar Science Fair Project Ideas
Salt and sugar are two materials you probably have on hand. There are many science fair projects you can do with either of these ingredients. Here's a list of ideas to help get you started on your science fair project.

Salt and Vinegar Crystals
Salt and vinegar crystals are easy-to-grow non-toxic crystals that you can grow in a rainbow of colors. This crystal growing project is especially good for kids or beginners looking for quick and easy crystals.

Salt Formation Chemistry
Learn about the chemistry behind salt formation, including neutralization and hydrolysis reactions.

Science -ology Quiz
How well do you know the difference sciences ending with the -ology suffix? Test yourself with this fun multiple choice quiz.

Science Fair Project Help
Science fair projects are a great way to learn about experimentation, the scientific method, and science concepts. However, it can be hard to find an idea or get answers to questions once you get started. Here is a collection of resources to give your project the winning edge.

Science Fair Project Quiz
Get information about what makes a good science fair project, then test your understanding with this multiple choice quiz.

Science Hangman Game
Here's a hangman game, just for fun, using scientific terms, types of sciences, and names of scientists from all disciplines. It's a very broad category. Can you guess the word in time?

Scientific Law, Hypothesis, Theory Definitions
Words have very specific meanings in chemistry and other sciences. Learn about the difference between a scientific law, hypothesis, and theory. Examples are provided for each term.

Scientific Method Quiz
Do you really understand what the scientific method is and how to apply it? Here's a ten question multiple choice quiz you can take to test your knowledge.

Searching for Extraterrestrial Life
There's some serious chemistry involved in the search for life on other planets (or gas clouds or asteroids or comets). However, other disciplines come into play as well, such as robotics, aeronautics, biology, geology, and economics. Here's an overview of how we search for ETs.

Secret Formula or Equation?
Here's a formula or equation submitted by a reader. He says he's been carrying it around in his wallet for twenty years and that at least one man's death was linked to the content. Does the equation still have significance today? You be the judge.

Seed Crystal Instructions
A seed crystal is a small single crystal that you use to grow a much larger crystal from a saturated crystal solution. This is how you can grow a seed crystal yourself.

Shampoo Recipe
You can make your own shampoo from scratch using simple ingredients and a little chemistry know-how. Here's a shampoo recipe to get you started.

Sharpie Pen Tie Dye
You can create a pattern resembling tie-dye using colored Sharpie pens and rubbing alcohol. It's a fun and educational project that is great for kids.

Significant Figures in Measurements and Calculations
This article discusses the use of significant figures in taking measurements and performing calculations. Learn about significant figures, uncertainty, accuracy, precision, rounding, and truncating. Losing significant figures and effects of exact numbers are also described.

Silly Putty Chemistry
Learn about the history of Silly Putty, how it works, how to make your own, and what you can do to explore the interesting properties of this viscoelastic liquid.

Single Bond Energies
This is a table of single bond energies in units of kJ/mol at 25°C. Use these values to predict whether a reaction will be endothermic or exothermic and to calculate change in enthalpy for gases.

Sir Joseph John (J. J.) Thomson (1884–1918)
J.J. Thomson discovered the electron while studying the electricity in a cathode ray tube (CRT).

Slime Step-By-Step Instructions
Slime is easy and fun to make, plus it only requires glue, borax, and water. Here are step-by-step instructions for making classic slime, complete with photos.

Smoke Bomb Instructions
You can easily make a smoke bomb using inexpensive materials to produce safe smoke.

Smoking Fingers Trick
Make your fingers smoke when you rub them together and glow in the dark. All you need is a matchbox and a way to burn the striker portion.

Snow Globe Using Benzoic Acid
Snow made from water crystals melts at room temperature, but snow made from benzoic acid crystals will still be decorating your snow globe when the weather warms up. Here's how to make a snow globe by precipitating benzoic acid to make the 'snow'.

Snow Ice Cream Recipes
Here is a collection of several quick and easy recipes for ice cream you can make using snow.

Snowflake Chemistry
Here are answers to common questions about snowflakes. Learn how snow forms, what shapes snowflakes take, why snow crystals are symmetrical, whether no two snowflakes really are alike, and why snow looks white!

Snowflake Photo Gallery
Snowflakes take many forms. This is a photo gallery of snowflakes and ice crystals.

Snowflake Shapes
It may be hard to find two snowflakes that look identical, but you can classify snow crystals according to their shapes. This is a list of different snowflake patterns.

Solubility of Ionic Compounds in Water
Here's a table of the solubility rules for common ionic solids in water, as well as an explanation of the main factors which affect solubility.

Solubility Product Constants at 25 Degrees Celsius
This is a table of the solubility product constants for some common ions in aqueous solution at 25 degrees Celsius.

Solutions, Suspensions, Colloids, and Dispersions
Learn how to distiguish between solutions, suspensions, colloids, and dispersions. Get examples of the different types of mixtures.

Sparkler Instructions
Learn how to make your own sparklers, for Independence Day or New Years Day fun. Use your understanding of chemistry to color the sparks.

Spiders in Space
Columbia's STS-107 carried Australia's first animals into space. Learn about the Columbia spider experiment and the Skylab 3 experiment and visit links to ground-based research and space exploration.

Spooky Halloween Jack-o-Lantern
You can make spooky fog come out of your Halloween jack-o-lantern using a little dry ice. Here's how you do it plus a trick for getting the best effect.

Sports Drinks - Better than Water?
Are you exercising or sweating away under a summer sun? Find out what beverage to drink to get and stay hydrated. Do you think water is best? Are sports drinks worth the money? What about a beer? Here's what you need to know.

Sports Science Fair Project Ideas
There is a lot of science involved in sports. Combine your love of sports with science to come up with the perfect science fair project.

Standard State Conditions
Values of thermodynamic quantities are commonly expressed for standard state conditions, so it is a good idea to understand what the standard state conditions are.

States of Matter
Get definitions and examples of the main states of matter: solids, liquids, gases, and plasma.

Stink Bomb Recipes
Stink bombs smell terrible, but they are also fun. Here are instructions for how to use everyday materials to make your own stink bombs.

Stoichiometry Quiz
Stoichiometry is concerned with the proportions of elements that combine during chemical reactions. Test your understanding of stoichiomety with this fun multiple choice quiz.

Storm Glass Instructions
Use your knowledge of chemistry to make a storm glass to help you predict the weather.

Strength of Acids and Bases
Learn about strong and weak acids and bases. Get definitions and examples of each type.

Successful Science Fair Projects
Get help finding a subject, preparing a hypothesis, writing the report, and making a presentation for a science fair project. This guide is suitable for grade school through university level.

Sugar and String Crystal Easter Eggs
Sugar and string Easter egg ornaments are a fun family craft idea, plus you can include a lot of science in this project. You can make smaller hollow string ornaments to hang or put in baskets or you can make a large crystal egg to use as an Easter basket.

Sugar Crystal Growing Problems
Sugar crystals, also known as rock candy, are great crystals to grow because they are beautiful, can be grown in any color of the rainbow, and because you can eat them. They aren't always the easiest crystals to grow. Here's how to solve problems growing sugar crystals.

Sulfur Hexafluoride Demonstrations
Sulfur hexafluoride is a non-toxic, invisible gas that you can use to perform interesting chemistry demonstrations. Breathe it in and make your voice much deeper when you talk. Pour it into a container and float an airplane or a ship on 'nothing'.

Surface Area and Volume Formulas
Surface area and volume formulas are part of the math used in common science calculations. You may need to calculate surface area and volume to determine density, pressure and concentration, for example. While it's a good idea to memorize these formulas, here a list of surface area and volume formulas to use as a handy reference.

Tattoo Ink Chemistry
Tattoo inks aren't regulated by the US FDA, so what you don't know can hurt you. This 3-part article examines the pigments, carriers, and other chemistry-related issues concerning tattoo inks and their toxicity. Instructions for making your own tattoo ink are provided.

Tear Gas
Learn about what tear gas is and how it works.

The Scientific Method
Science fair and research projects apply the scientific method. Here's an informal explanation of the scientific method and how it is used.

Timeline of Element Discovery
Use this table to look up the date an element was discovered and the name(s) of its discoverer. Links to additional element facts are provided, too.

Tin Crystal Growing Instructions
It's easy to grow crystals of tin metal using a simple replacement reaction. You can see the crystals in an hour or so, or leave them overnight for more/larger crystals.

Titration Basics - Acids Bases and Buffers
Grasp the basic chemical concepts of titration, a technique used to determine the molarity of an acid or a base.

Top Calculators
Choices, choices! Read this to help select a scientific, graphing, printing, programmable, desktop, solar, or wallet calculator. Then compare prices for your favorites.

Top Chemistry Demonstrations & Activities
This is the list of my personal favorite chemistry demonstrations and activities. They tend to involve pretty colors, fire, or ice. Some projects require adult supervision or access to a chemistry lab. Others are easy and safe enough for kids to perform.

Top Chemistry Projects for Bored Kids
Are you searching for something fun and educational to do that suitable for kids? Here are some great chemistry activities and projects to get you started. They are safe and use easy-to-find materials.

Top Chemistry Projects You Can Do at Home
Don't worry if you don't have a chemistry lab. These projects use materials you can find around the house.

Top Chemistry Sets
There are some truly exceptional chemistry sets out right now! Many of these kits introduce fundamental concepts through fun themes, such as 'slime' or 'glowing chemistry' or 'edible chemistry', while other sets are safer versions of the standard chemistry sets.

Top Crystal Growing Kits
Here are some kits for growing your own crystals. There are big kits with multiple crystal types, non-toxic kits for younger explorers, pre-sealed crystal globes, and unopened geodes!

Top Portable Household Water Filters
Water filtration pitchers are a convenient, economical method of improving quality and taste of potable water. Most filters effectively remove chlorine and heavy metals, but differ in capability to remove pathogens and organic compounds. Availability is also an important factor in selecting a filter. Check here for my top water pitcher picks!

Top Science Fair Project Books
This is a collection of top-rated science fair project resources for students, parents, and educators. There are books that describe experiments, a CD-ROM packed with thousands of pages of ideas, and reference materials for making posters, giving presentations, and understanding the judging process.

Top Science Movies
These are the top science movies of all time, as rated by your About Chemistry Guide. I'm pretty sure my list differs from conventional wisdom, so justifications for my film choices are provided.

Top Science Toys
Chemistry sets, metal detectors, rock tumblers, telescopes, microscopes, rockets, creatures, and more! These are some great educational toys, along with helpful selection tips and price comparisons.

Toxic Elements
Here's a list of elements that are toxic or poisonous and have no known nutritional value.

Learn about the process of translation, in which the genetic code of mRNA is used to produce amino acids that will ultimately become proteins.

Tumbling Jewelry
You can use a rock tumbler to polish and clean your jewelry. Tumblers are great for smoothing rough edges on metal components, such as jump rings and earwires.

Turning Lead into Gold
Learn about transmutation, the holy grail of alchemy. Can one chemical be changed into another? Is it worth the effort?

Types of Chemical Bonds
Learn about the different types of chemical bonds and the forces that affect the way electrons are shared.

Types of Chemical Reactions
Learn about the different types of chemical reactions and get examples of the reaction types.

Types of Inorganic Chemical Reactions
There are four main categories of inorganic chemical reactions. Can you name them all? Here they are, along with examples of each type.

Ultimate Colored Smoke Bomb
Make a smoke bomb that billows clouds of brightly colored smoke. This project is easy and safe enough to at home. Adult supervision is required.

Unit Conversion Worksheets
Use these printable worksheets to practice unit conversions. These pdf questions and answers will test your understanding of metric-metric, metric-English, and temperature conversions.

Using Material Safety Data Sheets
Material Safety Data Sheets (MSDSs) aren't just for chemists! This guide for the non-technical consumer defines MSDSs, describes why you should know how to use them, tells how to find them, and outlines typical uses. Links to several MSDS databases are included.

Valences of the Elements
The valences aren't just those you see in the columns of the periodic table! Check out this chart of element valences to help determine potential chemical reactions.

Violet Fire
It's very simple to make violet or purple fire. All you need are two easy-to-find ingredients.

Vitamin C Determination by Iodine Titration
Use this redox-based iodometric titration to determine the amount of Vitamin C or ascorbic acid in juice and other samples.

Vitamins May Hurt Your Health
Your multivitamin may contain more or less nutrients than you think, plus may include some nasty contaminants.

Water - Wine - Milk - Beer Chemistry Demo
Here's a color change chemistry demo in which a solution seems to change from water to wine to milk to beer simply be being poured into the appropriate beverage glass.

Water Filters that Remove Fluoride
This is a compilation of online vendors and manufacturers of water filters designed to remove tap water. A variety of filter types and price ranges are covered. Tabletop, undersink, and refrigerator models are all available.

Water into Wine Demonstration
Turn a clear liquid into a red liquid, then back to clear again. This demonstration is commonly called turning water into wine or blood, and can be used to demonstrate acid-base indicators.

Ways to Lower Reduce Exposure
Fluoride isn't only found in toothpaste and water. There are many everyday sources and several steps you can take to lower your exposure.

What Are Some Careers in Chemistry?
Chemistry isn't just for chemists! Here's a nice long list of chemistry-related careers, along with a discussion on how your degree impacts your employment options.

What Are the Elements in the Human Body?
Do you know the chemical composition of the human body? Here's the list of elements, given in percentage according to weight.

What Causes Rigor Mortis?
Dead bodies are sometimes referred to as 'stiffs' for a reason! Learn what rigor mortis is and find out why it happens.

What Is a Chemical Element?
Get the definition for a chemical element.

What Is a Chemical?
Are you wondering what makes a chemical a chemical? Here's the answer to this frequently asked chemistry question.

What Is a Crystal?
Get the definition for a crystal and learn about some common types of crystals.

What Is a Mole and Why Are Moles Used?
No, we're not talking about the small burrowing mammal! Here's a look at a standard unit in chemistry and why it's used.

What Is a Neutron Bomb?
Learn what a neutron bomb is, how it works, and about a neutron bomb's strategic uses.

What Is Absolute Zero?
Learn about absolute zero and the Kelvin and Celsius temperature scales.

What Is Activated Charcoal and How Does it Work?
Activated charcoal isn't the same as your average barbeque briquette! It's a special type of carbon. Learn what activated charcoal is and why it is used in filters and medicines.

What Is Bleach and How Does It Work?
Learn what a bleach is, get examples of different types, and find out how bleach works.

What Is Chemical Engineering? What Do Chemical Engineers Do?
Are you confused about how chemical engineering differs from pure chemistry or other types of engineering? Here's an explanation of what chemical engineering is and what chemical engineers do.

What Is Distillation?
Distillation is a common chemistry process used to separate materials by changing their states of matter. Learn more about how the process works and find out about different types of distillations.

What Is Dry Ice?
Do you know what dry ice is? Learn about dry ice and find fun projects that use dry ice.

What Is Earth Day?
Find out what Earth Day is all about, when it is, and how it started.

What Is in Chewing Gum?
Learn about the ingredients in chewing gum and find out whether it's true gum stays in your stomach seven years if you swallow it.

What Is Radioactivity? What is Radiation?
Learn about natural and induced radioactivity and alpha, beta, and gamma radiation.

What Is Red Mercury?
Is it a secret, wildly explosive compound used to make deuterium-tritium fusion bombs for use by terrorists? Maybe there's a more conventional explanation...

What Is the Chemical Composition of Air?
Learn about chemical composition of the Earth's air. Percentages of the most common compounds are given, according to volume.

What Is the Clean Air Act?
You've probably heard about the Clean Air Acts and can figure out they have something to do with air pollution, but what else do you know about Clean Air Act legislation? Here's a look at the Clean Air Acts and answers to some common questions about them.

What Is the Clean Water Act?
Here's a look at what the Clean Water Act is and how this legislation is intended to address water pollution.

What Is the Coastal Dead Zone?
The coastal dead zone makes news headlines from time to time because it's implicated in fish death and may be a consequence of global warming and pollution. Do you know what the dead zone is?

What Is the Difference Between a Scientist and an Engineer?
Scientist versus engineer: are they the same? Different? Here's a look at the definitions of scientist and engineer and the difference between a scientist and engineer.

What Is the Difference Between Baking Powder & Baking Soda?
Learn about the difference between these two common cooking ingredients, the effect of substitutions, and find out how you can use baking soda to make your own baking powder.

What Is the Greenhouse Effect?
Learn what the greenhouse effect is and how it is related to climate.

What Is the IUPAC and What Does It Do?
Find out what the IUPAC is and learn a little about about what the IUPAC does.

What Is the Lightest or Least Dense Solid?
I'll give you a hint: it isn't styrofoam! The world's lightest solid resembles a sort of solid smoke, with a density of only 19 grams per liter.

What Is the Most Abundant Element?
The elemental composition of the universe and the earth's crust are very different! How different? Take a look...

What Is the Most Bitter Compound?
I've had some scorched coffee that I'm sure should have qualified for this award, but it turns out there's a real answer to this question of taste. Do you know what it is?

What Is the Most Poisonous Chemical Compound?
How poisonous something is depends a lot on how it's administered and a several other factors, but this list will give you a general look at some of the most toxic substances known to man.

What Is the Smelliest Chemical?
There are some man-made chemicals with a stench well beyond the gentle perfume of dirty gym socks and skunk spray. Do you know the names of these super-stinkers?

What is the State of Matter of Fire?
What is the state of matter of fire or flame? Is it a liquid, solid, or gas? Learn the answer to this question and get information about the chemistry of fire.

What Is the Strongest Acid?
Do you know what the strongest acid is? I'll give you a hint. It's not hydrochloric acid nor is it sulfuric acid.

What Is the Sweetest Compound?
Did you know there are sweeteners that are 200,000 times sweeter than table sugar? Take a look at this list to find out how your favorite sweetener rates.

What Is the Volume & Chemical Composition of Blood?
Do you know how many liters of blood are in your body? How about what's in your blood? Let's learn about the chemistry of human blood.

What Is the World's Most Venomous Insect?
The most venomous insect isn't some rare, exotic rain forest creature. You may have them in your own yard. Can you name guess what it is?

What Makes Lead Poisonous?
You probably know that lead is toxic, but do you know what makes it poisonous? Here's an explanation of what lead does in your body that makes it such a health hazard.

What Materials Glow Under a Black or Ultraviolet Light?
Black lights emit ultraviolet radiation, giving certain materials an eerie glow. Which materials? You can do a little experimental research or you can check out this list!

What Was Project Stormfury? Can Cloud Seeding Dissipate Hurricanes?
One way scientists have tried to lessen the severity of hurricanes is by seeding the clouds with silver iodide. This research program was Project Stormfury. Learn whether cloud seeding worked and why the program was discontinued.

What You Need to Know about Carbon Monoxide Detectors
Carbon monoxide poisoning is the leading cause of accidental poisoning deaths in America. Carbon monoxide detectors are available, but you need to understand how they work and what their limitations are in order to decide whether or not you need a detector and, if you purchase a detector, how to use it to get the best protection.

Which Gasoline Should You Buy?
Here's a look at what you need to know before you buy gasoline. Learn about octane ratings and gasoline formulations so you'll know which gas to buy at the pump.

Which Mad Scientist Are You?
If you were a famous mad scientist, which mad scientist would you be? Take this fun multiple choice quiz to find out.

White Smoke Chemistry Demonstration
Learn how to perform the white smoke chemistry demonstration, in which a cloud of ammonium chloride crystals are produced from reacting ammonia and hydrochloric acid.

Who Was Gaylord Nelson?
There's a good chance you may have heard of Gaylord Nelson, especially in connection with Earth Day, but do you know who he was?

Why Are Babies Born with Blue Eyes?
Do you know the answer? It's a matter of chemistry as much as biology. I've included other factoids about eye color, including some that may surprise you.

Why Cut Apples Pears Bananas and Potatoes Turn Brown
Learn why apples, pears, bananas, potatoes, and other fruits and vegetables turn brown when they are cut or damaged.

Why Do a Science Fair Project?
There are excellent reasons why you would want to do a science fair project, even if it isn't for a grade.

Why Do Clothes Wrinkle?
Learn why clothes wrinkle and how permanent press fabrics work. It's a matter of polymer chemistry and chemical bonding.

Why Do Leaves Change Color in the Fall?
Find out why leaves change color in the fall. Learn about the different pigments found in leaves and how bright autumn foliage is produced.

Why Do Onions Make You Cry?
Find out why you cry when you cut onions and how you can keep it from happening.

Why Do Students Fail Chemistry?
Worried about failing chemistry? Here's a look at the main reasons why students fail. Avoiding these common problems could be a key to science class success!

Why Does Ice Float?
Learn about hydrogen bonding and density to understand why ice floats on water.

Why Does the Pool Turn Blonde Hair Green?
Do you think it's the chlorine in the swimming pool that turns blonde hair green? Guess again.

Why I Oppose Fluoridation of Public Drinking Water
Anne Helmenstine's reasons for opposing the fluoridation of public drinking water.

Why Is It Harder to Rinse off Soap with Soft Water?
Soap lathers better in soft water, yet it's harder to rinse off than if you rinsed with hard water. Why? The answer lies in understanding the chemistry of soft water and soap.

Why is Stainless Steel Stainless?
Learn about the chemistry of stainless steel. This article also includes descriptions of the different types of stainless steels, comments on passivation, and numerous links to sites offering related information.

Why the Flu Vaccine Doesn't Work
A study conducted by the CDC indicates that getting the flu vaccine doesn't protect you against cold, flu-like illness, or even the flu. Surprised? Here are some reasons why the vaccine may not work.

Why You Should Get Your Doctoral Degree
If you are studying chemistry or another science, will you stop with a Bachelor's, Master's, or Doctoral degree? Read about the advantages to getting a Ph.D.

Women in Chemistry
Women have made many important contributions to the fields of chemistry and chemical engineering. Here's a list of female scientists and a description of the research or invention that made them famous.

Working from Home - Chemistry & Other Sciences
Are you looking for a way to work at home in the sciences? Here is a list of employment options, with notes on what to expect when you make the transition to home and ideas for staying up-to-date in your field.

Yeast & Hydrogen Peroxide Volcano
Here's how to make a safe and easy chemical volcano using two common inexpensive household ingredients.

You and Your Cat and Mad Cow Disease
Do you think you have a handle on the Mad Cow Disease issue? Here's a detailed guest article, written by microbiologist Eve Riser-Roberts, Ph.D., that may shake things up a bit for you. Although the article is slanted toward dangers in pet food, it contains a lot of controversial information pertaining to human risk and infection.

Hot Chemistry Topics
Are you wondering what's hot in the field of chemistry? Here's a look at some hot chemistry topics from About.com's Chemistry forum. See submissions

How to Build a Bomb - Feinstein Amendment SP 419
Learn about Feinstein Amendment SP 419 as it relates to the distribution of bomb-making instructions.

Is Everything a Chemical?
Chemicals aren't just exotic substances found in a chemistry lab. Here's a look at what makes something a chemical and the answer to whether everything is a chemical.

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