Introduction
Have You Ever Wondered
by Geoffrey Giller

Section 1: It’s Elementary

1.1    Does Plutonium Ever Occur Naturally?
         by John W. Poston and Gregory A. Lyzenga
1.2    Why Are Graphite and Diamond So Different when Both Are Made of Pure Carbon?
         by Miriam Rossi
1.3    How Do Scientists Detect New Elements that Last Only Milliseconds?
         by Todd M. Hamilton
1.4    How Are the Abbreviations of the Periodic Table Determined?
         by Michael R. Topp
1.5    Why Do Certain Elements Change Color over a Flame?
         by Stephen Reucroft and John Swain

Section 2: Terms of Art

2.1    What Is an Exothermic Reaction?
         by Gerald R. Van Hecke
2.2    What Is Chemiluminescence?
         by Joseph Merola
2.3    What is Charles' Law?
         by Theodore G. Lindeman

Section 3: Everyday Chemistry

3.1    How Do Fire Extinguishers Work?
         by William L. Grosshandler
3.2    How Does Chlorine Kill Bacteria and Other Harmful Organisms?
         by Jon J. Calomiris, Keith A. Christman and Leslie E. Dorworth
3.3    Why Do Ice Cubes in my Freezer Develop Spikes?
         by Stephen Morris
3.4    Why Do Apple Slices Turn Brown after Being Cut?
         by Lynne McLandsborough
3.5    How Is Caffeine Removed to Produce Decaffeinated Coffee?
         by Fergus Clydesdale
3.6    How Do Fireworks Work?
         by Paul Nicholas Worsey
3.7    How Do Air Bags Work?
         by Joseph S. Merola
3.8    Why Does a Shaken Soda Fizz More Than an Unshaken One?
         by Chuck Wight
3.9    How Are Polymers Made?
         by Frank N. Kelley
3.10    What Substances Have a Lower Solubility when Heated?
         by Ted Lindeman

Section 4: The Air We Breathe

4.1    How Can Global Warming Be Traced to Carbon Dioxide?
         by Pieter Tans
4.2    Why Not Split Harmful Carbon Dioxide into Harmless Carbon and Oxygen?
         by James E. Miller
4.3    What Is the Weight Ratio of Carbon Dioxide Released to Fuel Burned?
         by Susan Trumbore
4.4    Why Is There an Ozone Hole in the Atmosphere but Too Much Ozone at Ground Level?
         by Ross J. Salawitch

Section 5: Body Chemistry

5.1    Why Does Inhaling Helium Make Your Voice Sound Strange?
         by Craig Montgomery
5.2    Does Potassium Iodide Protect People from Radiation Leaks?
         by Larry Greenemeier and John Boice
5.3    Why Do Some Chemicals Have "Left" and "Right" Forms?
         by Willard M. Welch, Jr. and James R. Paulson
5.4    How Did They Find the Chemical that Makes Your Pupils Dilate?
         by Nikhil Swaminathan and Donald Mutti
5.5    What Is Junk DNA, and What Is It Good For?
         by Wojciech Makalowski
5.6    How and Why Do Fireflies Light Up?
         by Marc Branham