Re: Why did tempera paint and Kool-Aid react?

The tempera paint contains chalk.  The chalk is used as a filler to make 
the paint thicker. Chalk is composed of limestone, which is actually a 
chemical called calcium carbonate.  The Kool-Aid contains citric acid, 
which gives it the lemon flavor.  This acid reacted with the chalk and 
formed carbon dioxide gas.  Carbon dioxide, or CO2 is what gives soda its 
fizz.  It is the same thing that happens when you mix vinegar with baking 
soda.  If you mix chalk powder with vinegar, then it wll also fizz.  Try 
mixing other flavors of Kool-Aid with the tempera paint.  Some color like 
cherry, might not fizz. The white rubbery stuff was probably egg-white 
which was cooked by the acid in the Kool-Aid.  Egg-white is used to amke 
tempera paint.  Certain chemicals can cook egg-white without heat.  Try 
adding soime egg white to the Kool-Aid instead of paint.  I haven't tried 
this myself, but it might work.  You might also try egg-white with 
vinegar, but I haven't tried that either. Try painting with that foaming 
mess, maybe it will give an interesting texture. Have fun