An explanation on why carbon forms when you add sulfuric acid to sugar.
Well, sugar (sucrose) is made up of hydrogen, oxygen and carbon atoms. When the sulfuric acid comes in contact with the sucrose molecule, a chemical reaction takes place, and as well as being very hot, the atoms of the molecule start to break apart.
Now that the atoms are not together, there is just hydrogen, oxygen and carbon remaining. Hydrogen and oxygen are both gases, and since nothing is holding them back, they float away. Now that all the hydrogen and oxygen is gone… that leaves carbon remaining. And, that’s why when you mix sulphuric acid and sugar, it leaves carbon.
This science experiment is simple, add two things and watch the chemical reaction take place. First when you mix them, it begins to turn yellow. Then it turns black, and then it starts to bubble up. The bubbles then become solid, and they keep getting higher and then it’s higher than the tube it was in. During this, steam is coming off it. It smells a lot like caramel as well. Here’s a YouTube video of the experiment: http://www.youtube.com/watch?v=nqDHwd9rG0s