Sulfuric Acid - A Dehydrating Agent

Описание: Concentrated sulfuric acid is a strong dehydrating agent, which is the reason it is corrosive to living material. One way of writing the formula of table sugar is C12H22O11.
Another way to write the formula is C12(H2O)11.
This shows that the carbohydrate is made of carbon and water.

Here is some table sugar, and here is a bottle of concentrated sulfuric acid. I will mix some of the acid with the sugar, and let's watch what happens. This will take several minutes.


Notice that the color of the sugar is changing a little.


Now do you see the steam rising ?


The chemical reaction you are seeing is the dehydration of the sugar to water vapor and pure carbon. There is so much energy being released that the water turns to steam and makes the carbon molecules separate, much like bread rises.
C12(H2O)11  12 C + 11 H2O(­g) + Energy



The carbon becomes charcoal. The sulfuric acid also eventually evaporates as water vapor and sulfur trioxide gas.

H2SO4(l) + energy  H2­­O(g) + SO3(g)

This is a very expensive way of making charcoal. I used about fifty cents' worth of sugar and one dollar's worth of sulfuric acid to make less than fifty cents' worth of charcoal. Plus this charcoal is not dry enough to take and burn immediately.