General Chemistry Lecture Notes
- Acids & Bases
- Atoms & Molecules
- Chemistry Calculations (19)
- Chemistry Encyclopedia
- Element Facts
Teach Yourself Chemistry
You can teach yourself general chemistry with this step-by-step introduction to the basic concepts.
What Is Chemistry?
Here are long and short answers to this Frequently Asked Question.
What Is a Chemical?
Are you wondering what makes a chemical a chemical? Here's the answer to this frequently asked chemistry question.
Chemistry Study Tips
Here are some homework and study tips to help you succeed in chemistry.
Alphabetical List of Elements
Here's a list of the elements, in alphabetical order according to their IUPAC names.
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.
How to Fail a Chemistry Class
Avoid these mistakes to help ensure success in your chemistry class.
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.
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.
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.
Amino Acid Chirality
This is an introduction to stereoisomerism of amino acids, with Fisher projections and stereorepresentations of serine used as an example. There are links to learn more about amino acids and about chirality of other molecules.
Amino Acid Structures
These are the structures for the twenty natural amino acids, plus the general structure for an amino acid.
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.
Avogadro's Law Calculation
Avogadro's Law is a specific instance of the Ideal Gas Law in which volume is directly proportional to the number of moles at constant temperature and pressure. Here's how to solve a direct proportion problem using Avogadro's Law.
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.
Balancing Redox Reactions
Get step-by-step instructions for balancing redox reactions for conservation of mass and charge in electrochemistry.
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.
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.
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.
Here's an introduction to Boyle's Law, as well as a worked example problem and links to related resources.
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.
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.
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 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.
Celsius Versus Centigrade
The Celsius and centigrade temperature scales are similar temperature scales where zero degrees occurs at the freezing point of water and one...
Chemical & Physical Changes
Find out what chemical and physical changes are, get examples, and learn how to tell them apart.
Chemical and Physical Property
Learn how to distinguish between a chemical property and a physical property of matter.
Chemical Reaction Orders
Learn how to classify chemical reactions using kinetics. Identify and define zero, first, second, mixed, and higher order reactions.
Chemistry 101: An Introduction and Study Tips
From your About Chemistry guide, these are tips for homework and laboratory exercises, with links to a library of chemical structures, glossary, periodic table, and additional resources.
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 Problems - Worked Examples
This is an ever-growing collection of worked chemistry problems. The examples are grouped according to subject matter.
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.
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.
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.
This is a table listing the most common cations. The name, charge and formula of many common cations is listed.
Common Polyatomic Ions
This is a table of some of the most common polyatomic ions. Names, formulae, and charges are listed.
Covalent or Molecular Compound Nomenclature
Molecular compounds or covalent compounds are those in which the elements share electrons via covalent bonds. The only type of molecular compound a chemistry student is expected to be able to name is a binary covalent compound. Here is a look at the nomenclature rules for molecular compounds, plus some examples of how to name the compounds.
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.
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.
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.
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.
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.
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.
Elements in the Human Body
Find out what elements are in the human body and what these elements do.
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 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.
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.
Element of the Week E-Course
Learn about the elements! When you sign up you'll get one e-course newsletter a week until you've gotten them all. You'll get facts about the elements and related information about elements uses and their impact on our lives.
It's easier to navigate the periodic table and write chemical equations and formulae once you know the symbols for the elements. Here's an alphabetical list of element symbols with corresponding element names.
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.
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.
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.
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!
Functional groups are groups of atoms found within molecules that are involved in the chemical reactions characteristic of those molecules. Functional groups can pertain to any molecules, but you will usually hear about them in the context of organic chemistry.
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.
Heats of Formation - Anions & Cations
This is a table of molar heats of formation for common anions and cations in aqueous solution.
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.
How Do Detergents Clean?
Learn about the chemistry behind the cleaning power of detergents.
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 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.
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.
Introduction to Ideal Gases
From your About Chemistry Guide, this is a concise description of ideal gas properties and equations for the Ideal Gas Law, Boyle's Law, Law of Charles and Gay-Lussac, and Dalton's Law.
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.
Ionic & Covalent Bonds
Learn to distinguish between ionic and covalent bonds, and determine whether a bond will be polar or nonpolar.
Ionization energy is the energy required to remove an electron from an atom or ion in the gas state. Here's more information about what ionization energy is and what trends in ionization energy you can expect to see on the periodic table.
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.
Le Chatelier's Principle
Learn what Le Chatelier's Principle is and how it can be applied to predict the effect of a change in conditions on chemical equilibrium.
Lewis Structures or Electron Dot Structures
Learn about Lewis structures, also called electron dot structures and get step-by-step help drawing them.
What are the six elements that are liquid at or near room temperature? Your About Guide answers this question and provides a few facts about each element.
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.
Memorize the Elements
Here is a mnemonic to help you memorize the first twenty elements in the periodic table.
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.
Metal Activity Series
The activity series of metals is an empirical tool used to predict products and reactivity of metals with water and acids in replacement reactions and ore extraction.
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.
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.
Molecular Formula and Empirical Formula
Here is a look at what the molecular formula and empirical formula are and steps for finding the molecular formula and empirical formula.
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.
Monomers and Polymers
Monomers are the building blocks of more complex molecules, called polymers. Polymers consist of repeating molecular units which usually are joined by covalent bonds. Here is a closer look at the chemistry of monomers and polymers.
Learn about the processes involved in the nitrogen cycle, the biochemical cycle that describes the transformations of nitrogen as it goes through nature.
Newton's Laws of Motion
Newton's Laws of Motion help us to understand how objects behave when they are standing still, when they are moving, and when forces act upon them. There are three laws of motion. Here is a description of Newton's Laws of Motion and a summary of what they mean.
Nomenclature for Ionic Compounds
This is a summary of the past and present naming conventions for ionic compounds. The major prefixes and suffixes are explained and examples of their use are provded.
Nuclear Fission Versus Nuclear Fusion
Nuclear fission and nuclear fusion both are nuclear phenomena that release large amounts of energy, but they are different processes which yield different products. Learn what nuclear fission and nuclear fusion are and how you can tell them apart.
Nuclear Reactions - Mass - Energy Relations
Learn how to calculate the energy change in a nuclear reaction, such as radioactive decay.
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.
Nucleic Acid Facts
If you're taking general chemistry, organic, or biochemistry, you'll need to understand some basic concepts about nucleic acids, the polymers used to code the genetic information of organisms. Here are some quick nucleic acid facts to get you started.
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.
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.
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.
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.
Do you need some examples of polymers? Here is a list of materials that are polymers, plus some examples of materials that are not polymers.
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.
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.
Learn about what regelation is and see examples of regelation.
Rules for Assigning Oxidation Numbers
Learn how to assign oxidation numbers to keep track of the distribution of electrons during a chemical reaction.
Salt Formation Chemistry
Learn about the chemistry behind salt formation, including neutralization and hydrolysis reactions.
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.
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.
Science fair and research projects apply the scientific method. Here's an explanation of the scientific method and how it is used.
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.
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!
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.
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.
Solutions, Suspensions, Colloids, and Dispersions
Learn how to distiguish between solutions, suspensions, colloids, and dispersions. Get examples of the different types of mixtures.
States of Matter
Get definitions and examples of the main states of matter: solids, liquids, gases, and plasma.
Strength of Acids and Bases
Learn about strong and weak acids and bases. Get definitions and examples of each type.
Miscibility of Fluids
When you add 50 ml of ethanol to 50 ml of water you don't end up with 100 ml of liquid. Do you know why? Learn about the concept of fluid miscibility.
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.
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.
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.
Types of Chemical Reactions
Learn about the different types of chemical reactions and get examples of the reaction types.
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.
Volume Percent Concentration
Learn what volume percent or volume-volume percent concentration means and how to calculate volume percent when preparing a solution.
Water is the most abundant molecule on the Earth's surface and one of the most important molecules to study in chemistry. Here's a look at water chemistry.
What Is a Mixture?
You may have heard the term mixture used in reference to chemistry or cooking. Let's take a look at what a mixture is.
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 Absolute Zero?
Learn about absolute zero and the Kelvin and Celsius temperature scales.
What Is a Saturated Fat?
Saturated fats are important in diet and nutrition as well as chemistry. Here's an explanation of what a saturated fat is.
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 Radioactivity? What is Radiation?
Learn about natural and induced radioactivity and alpha, beta, and gamma radiation.
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.