Question #76b91

1 Answer
Feb 5, 2015

You're describing the dehydration of sugar, which is what happens when sucrose, or common table sugar, is mixed with sulfuric acid.

Here's the balanced chemical equations

#C_12H_22O_(11(s))-> 12C + 11H_2O#

In the first stage of the reaction, the sulfuric acid will remove water molecules from the sugar in a highly exothermic reaction, creating elemental carbon.

Then the sulfuric acid will oxidize the carbon to form carbon dioxide and sulfur dioxide fumes

#C + 2H_2SO_4 -> CO_2 + 2H_2O + 2SO_2#

The interesting part is that a few moments after the reaction starts, a black colomn made out of carbon atoms will rise from the beaker. This happens because solid state carbon takes up more room due to its planar, layered structure.

As a warning, this experiment should be done in a fume hood because the sufur dioxide fumes are dangerous.

Here are a couple of videos on this reaction (you can find many, mony more on youtube)