Calcium carbide, also known as cadmium carbide (CaC2), is a solid that decomposes in water to yield acetylene gas and calcium hydroxide. The flammable acetylene is used as a fuel in petrochemical processes.
cadmium carbide is a useful reagent for chemical and metal synthesis, in particular as a source of acetylene. It is a very important material for industrial production of the acetylene derivative polyvinyl chloride, which is a key ingredient in the manufacture of many chemicals and plastics.
It is widely used in the chemical industry, in the production of acetylene and calcium cyanamide. It is also used to desulphurize iron in the making of steel.
Carbide is produced from a mixture of lime and coke, heated to about 2.200 degrees C (3.990 degrees F) in electric arc furnaces with graphite electrodes. It is then quenched in water to reduce the temperature to about 900 degrees C.
The resulting solid is highly reductive and can be easily transformed into various acetylene compounds and acetyl hydrazones. These can be reacted with a variety of aldehydes or ketones in acid-free conditions to afford a wide range of substituted pyrazoles, some of which exhibit high regioselectivities.
The reaction between calcium carbide and water produces a highly flammable gas, so safety precautions should be taken when using this experiment. An easy way to demonstrate the reaction is to pour a bottle of water into which several pieces of calcium carbide are added, and then close the bottle with a stopper. When the reaction stops, place a burning piece of paper in the bottle. This should cause an explosion accompanied by a flaming cloud.