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Showing posts from March 11, 2010

Make Sugar & String Easter Eggs

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Here's a fun Easter project for you: crystallize sugar onto string to make an Easter egg basket or a special holiday decoration. The project is similar to growing rock candy crystals except these sugar crystals form much more quickly and are used to form a construction material rather than a tasty crystal treat. Transcript: How to Make Rock Candy Hi, I'm Dr. Anne Helmenstine for About.com. Have you seen brightly colored rock candy in a store or used to sweeten a drink? Rock candy is simply sugar crystals. I'm going to show you how you can make rock candy yourself, in any color or flavor you like. Are you ready? Let's get started. Rock Candy Ingredients The only two ingredients you need for rock candy are sugar and water, though you can add food coloring and flavoring if you want colored and flavored crystals.

This Day in Science History - March 10 - Jeremias Richter

March 10th is Jeremias Benjamin Richter's birthday. Richter was a German chemist who introduced the term stoichiometry to chemistry. He noticed the ratio of reactants by weight used in a chemical reaction was always the same. This lead to the law of equivalent or multiple proportions. This discovery was one of the first steps towards a new atomic model of chemical reactions. Stoichiometry and balancing chemical equations are basic principles learned early in chemistry. Find out how to balance chemical equations or test your knowledge of stoichiometry and find out what else occurred on

Disposable Toilet Turns Human Waste into Fertilizer

Did you know about 2.6 billion people (~40% of the world's population) do not have access to a toilet? Although this is a problem you hopefully don't encounter, it is a major health concern since untreated human feces contaminate the water supply and cause deaths from diarrhea. A Swedish company has a developed a new disposable toilet that it believes will help combat this problem by providing toilets to people at a price point they may be able to afford. The Peepoo is a biodegradable plastic bag that contains an inner gauze that has been coated with a film of urea. A person uses the Peepoo, ties up the bag, and then buries it. According to a New York Times article, the urea crystals kill the pathogens and break the waste into a safe fertilizer. The bags will sell for around 2-3 cents, which is about the same cost as an ordinary plastic bag. Anders Wilhelmson, inventor of the Peepoo, has tested the bags in India and Kenya, where slum dwellers dispose of waste by collecting i...

Disposable Toilet Turns Human Waste into Fertilizer

Did you know about 2.6 billion people (~40% of the world's population) do not have access to a toilet? Although this is a problem you hopefully don't encounter, it is a major health concern since untreated human feces contaminate the water supply and cause deaths from diarrhea. A Swedish company has a developed a new disposable toilet that it believes will help combat this problem by providing toilets to people at a price point they may be able to afford. The Peepoo is a biodegradable plastic bag that contains an inner gauze that has been coated with a film of urea. A person uses the Peepoo, ties up the bag, and then buries it. According to a New York Times article, the urea crystals kill the pathogens and break the waste into a safe fertilizer. The bags will sell for around 2-3 cents, which is about the same cost as an ordinary plastic bag. Anders Wilhelmson, inventor of the Peepoo, has tested the bags in India and Kenya, where slum dwellers dispose of waste by collecting i...

Liquid Element Pictures

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 If I asked you to name a liquid element, you'd probably say 'mercury', which is liquid at room temperature. So are a few other elements, plus just about any element can turn into a liquid if the temperature and pressure are right. Do you know which element is pictured here, yellow as a solid and melting into a red liquid?