Dehydration of Sugar by Sulfuric Acid

Sulfuric acid is a dehydrating agent and so when mixed with sugar it will dehydrate it. Sugar is composed of carbon, hydrogen, and oxygen, so when the sulfuric acid removes the hydrogen and oxygen you are left with carbon. The reaction is done by just mixing sugar with sulfuric acid. Caution should be taken as hot steam vapours as well as sulfur oxides are produced. You can smell the burned sugar and sulfur dioxide. You don't really want to inhale this.

For this experiment I used 25 grams of sugar and about 30 ml of H2SO4.



As you can see, the sugar basically covers the bottom of the 250 ml beaker and doesn't go too high. The sulfuric acid was then poured on. The mixture turns thick and brownish/black. I didn't stir so the reaction took a bit of time to start. When it did though it started steaming quite a bit. The sugar was black and bubbling, and a column of carbon could be seen to rise in the beaker. After a while the steaming subsided and the beaker was seen to be full of a carbon column.



The piece of carbon was then dumped into a larger beaker with sodium bicarbonate solution and was left to neutralize remaining acid. The carbon fizzed and floated in the water, as it is less dense.



I then took it out and left it to sit to be admired by all. Well no one really admired it, so it's just kind of sitting in my backyard. Nothing special, but it's fun in its own way.

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