May 20^th is Eduard Buchner's birthday. Buchner was a German chemist who worked with the process of alcohol fermentation. Fermentation is the process that occurs when a carbohydrate like sugar is broken into alcohol. Many fermentation processes involve yeast to increase the rate of fermentation and was believed to be the catalyst for the reaction. Buchner showed there were enzymes in the yeast, which he named zymase, that actually worked as the catalyst and not the yeast itself. This distinction was a step away from the popular philosophy of vitalism, in which biochemical reactions need biological catalysts, and was important enough to earn him the 1907 Nobel Prize in Chemistry.

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Have you ever wondered what the difference is between chrome and chromium? Chromium is an element. It is a hard, corrosion-resistant transition metal. Chrome, which you may see as decorative trim on cars and motorcycles or to harden tools used for industrial processes, is an electroplated layer of chromium over another metal. Either hexavalent chromium or trivalent chromium may be used to produce chrome. The electroplating chemicals for both processes are toxic and regulated in many countries. Hexavalent chromium is extremely toxic, so trivalent chrome or tri-chrome tends to be more popular for modern applications. In 2007 hexa-chrome was banned for use on automobiles in Europe. Some chrome for industrial uses remains hexa-chrome because the corrosion resistance of hexa-chrome plating tends to exceed that of tri-chrome plating.

It's interesting to note that prior to the 1920's the decorating plating on automobiles was nickel and not chrome.

A pyro or pyromaniac is someone with a fascination for fire, often characterized by setting fires without needing to heat or cook anything or just staring into flames, mesmerized. Medically, a pyromaniac suffers from a compulsion, but the everyday usage of a pyro refers to someone who just really really likes fire! With fun in mind, here is a new quiz for you. You may learn something about fire and the combustion chemical reaction or you may learn something about yourself... Take the quiz

Some people believed the world would end on May 19, 1910. The most famous comet, Halley's Comet, had returned to the night sky and would pass so close to the Earth that we would pass through its tail on May 19^th. What would the comet leave in our atmosphere? Astronomers hoped to answer that question with the relatively new technique of spectroscopy. Among the many chemicals found in the spectra, they found evidence associated with the poisonous gas, cyanogen.

Most scientists figured that the tails of comets were basically dust clouds and any particles of cyanogen would be few and far between so we wouldn't even notice. Others latched on to that 'what if?' and foretold the end of every living thing. As the day got closer, more people worried about 'what if?' and sales of "Comet Pills" to counteract cyanogen poisoning skyrocketed.

On the morning of May 20^th, no one had died from cyanogen poisoning, even the ones that did not take any Comet Pills.

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