May 26^th marks the passing of Ascanio Sobrero. He was the Italian chemist who discovered the process of making nitroglycerin. He found the explosive and unstable compound while adding glycerin slowly to a mixture of nitric acid. Nitroglycerin proved to be extremely powerful in small amounts and would be just as likely to injure or kill the person handling it. At the end of his life, he expressed regret for discovering it and all the injuries it created.

One of his students, Alfred Nobel added diatomaceous earth to the mixture to stabilize it and make it safer to handle. He called this invention dynamite. He also added it to another explosive, gun cotton, and created gelignite. These two inventions would be the basis of the fortune that would become the Nobel Foundation.

Find out what else occurred on this day in science history.

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Happy Memorial Day Weekend too! May 25th was selected as the date for Geek Pride Day or Nerd Pride day because May 25th was when the first Star Wars movie premiered back in 1977 (which you possibly knew, if you are a Star Wars geek). Chemists and chemical engineers don't necessarily consider themselves to be geeks or nerds, but the general public may assign that term, so if you are a scientist or an engineer, celebrate the holiday! Since it's Memorial Day too, I recommend engaging in the barbequeing and watching some fireworks, but show your geek spirit by making at least one of the fireworks yourself. I have recipes...

Cream of Tartar is potassium bitartrate, also known as potassium hydrogen tartrate, which has a chemical formula of KC₄H₅O₆. Cream of tartar is an odorless white crystalline powder.

Where Does Cream of Tartar Come From?

Cream of tartar or potassium bitartrate crystallizes out of solution when grapes are fermented during winemaking. Crystals of cream of tartar may precipitate out of grape juice after it has been chilled or left to stand or the crystals may be found on the corks of wine bottles where the wine has been stored under cool conditions. The crude crystals, called beeswing, may be collected by filtering the grape juice or wine through cheesecloth.

Cream of Tartar Uses

Cream of tartar is used primarily in cooking, though it is also used as a cleaning agent by mixing it together with white vinegar and rubbing the paste onto hard water deposits and soap scum. Here are some of the culinary uses of cream of tartar:

• Added to whipped cream after it has been whipped to stabilize it.
• Added to egg whites when whipping them to increase their volume and help them maintain peaks at higher temperatures.
• Added when boiling vegetables to reduce discoloration.
• One of the key ingredients in some formulations of baking powder, where it reacts with baking soda and an acid to produce carbon dioxide to promote rising of baked goods.
• Found with potassium chloride in sodium-free salt substitutes.
• Used to make icing for gingerbread houses.

Do you know of any additional uses for cream of tartar? If so, please post a response.

Baking Ingredient Substitutions | Copper Bowl for Whipping Egg Whites

On May 25, 1961, President Kennedy announced to congress the goal for the United States to land a man on the moon and bring him safely back by the end of the decade. This was the beginning of the Apollo program that did successfully land men on the Moon on July 20, 1969, before the end of the decade.

You can view the speech to congress or the full public announcement speech at Rice University later that Fall, or find out what else occurred on this day in science history.

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