Chemistry is the science of matter and the changes it undergoes during chemical reactions. In this section, learn about everyday chemistry, from chlorine beach to helium, and even why chocolate turns gray.
Crack cocaine, like many other illegal drugs, leads to addiction, death, increased crime rates and imprisonment. But this drug targets the inner city almost exclusively and possession or distribution of crack carries extremely harsh prison sentences.
Viagra is one of the best-known drugs of all time. Nearly every adult in America has heard of the drug and can tell you what it does. Find out how this high-profile medication works its magic.
One person lay in critical condition on Feb. 29, 2008, after the deadly biotoxin ricin was found in his Las Vegas hotel room. What is ricin, and why is it so dangerous?
Have you seen investigators on crime shows who spray some stuff on a "clean" carpet and suddenly -- blood stains! Well, of all the fictional technology on TV, it turns out this stuff is real! Find out how luminol reveals the blood.
My parents just came back from Belgium and they brought me several boxes of chocolates. Some of the candy is sort of grayish looking. Is it OK to eat?
Marijuana isn't just a recreational drug for hippies and philosophy majors -- its psychoactive history ranges from Egyptian mummies to modern U.S. politics. What's the big deal about this leafy, green plant?
I recently bought a pair of mirrored sunglasses and they are already scratched. Isn't there a way to make them scratch-resistant?
What is dye-sublimation printing? Why is it better for printing digital images than traditional ink-jet printing?
Biting on aluminum foil can be painful -- basically, when you bite on foil, you build a battery in your mouth. Ouch!
Smoking or chewing tobacco makes many people feel good, even mildly euphoric. It's the nicotine that produces the buzz. Find out how nicotine affects the human body and what makes it so addictive.
More than 2.3 billion people across the globe drink alcohol, but most don't consider it a drug. But if you've ever seen someone who's had too much, you know alcohol has profound effects on the mind and body.
We need oxygen to live, so it seems to me that if we got more oxygen, we would be better off. Is it harmful to breathe 100-percent oxygen? What will happen?
Why do newspapers turn yellow over time?
Rust is the common name for iron oxide, which is created when iron bonds with oxygen. In fact, pure iron is only rarely found in nature because it interacts with oxygen so easily.
Here's something to consider: The place you call home likely has walls and glass windows. Both are adept at keeping rain, snow and wind from bothering you in your abode. Only one, though, allows light to enter. Why is that?
Dynamite is simply some sort of absorbent material (like sawdust) soaked in nitroglycerin. But what makes this chemical so explosive?
Ever wondered exactly what they "artificial flavors" in your candy are, and why no specific ingredients are listed? Find out in this article.
If water is made up of hydrogen and oxygen, why can't we breathe underwater? It has to do with how molecules combine and how the human lung functions.
Chemical formulas provide a concise explanation for reactions. In this article, we explain the formula for the reaction in a smoke detector.
Helium is the second lightest element on the Periodic Table. How is helium created?
I recently used chlorine bleach to clean the siding on my house, and I was amazed at how well it worked! What is bleach? How does it remove stains? Is the chlorine in bleach the same as the chlorine in drinking water or in swimming pools? Is chlorine safe to use?
I have heard that carbon monoxide is extremely poisonous. Can you explain why?
What is dioxin? There's a lot of discussion going on in my town about dioxin and its dangers.
Scenario: A helium balloon is up against the ceiling one day, and the next day it's on the floor. Does the balloon fall because the helium leaks out, or because the helium molecules slow down due to decreased pressure?
If the idea of being completely knocked out by a cocktail of drugs while doctors operate on you freaks you out, you're not the only one. But that's not what anesthesia is all about it -- and it might scare you less if you understand how it works.