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Dehydration of Sucrose with Sulfuric Acid

Concentrated sulfuric acid is added to sucrose forming carbon, steam and sulfur dioxide.

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Narrative
Sucrose or common table sugar is mixed with concentrated sulfuric acid. The mixture is stirred. Soon an exothermic reaction takes places during which a column of carbon rises from the beaker and a cloud of steam and sulfur dioxide is produced. Concentrated sulfuric acid dehydrates sucrose to produce carbon and water. The heat of the reaction vaporizes the water causing the column of carbon to form.

Discussion
Sucrose (table sugar) is placed in a beaker and concentrated sulfuric acid added. Soon an exothermic reaction takes places during which a column of carbon rises from the beaker with a cloud of steam and sulfur dioxide.

The name carbohydrate derives from the formula of sugars such as sucrose (C12H22O11 or C12(H2O)11) in which the formula appears to be a hydrate of carbon. In the presence of concentrated sulfuric acid sucrose is dehydrated to produce carbon and water. The heat of the reaction vaporizes the water causing the column of carbon to form.