Write short notes on coal tar …

Coal tar (liquid): Coal tar is a mixture of different carbon compounds. It thick, black liquid with unpleasant smell. The fractional distillation of coal tar gives many chemical substances which are used in the preparation of dyes, explosives, paints, synthetics fibers, drugs, and pesticides. Some of these chemical substances are benzene, toluene, phenol and aniline. Naphthalene balls used to repel moth and other insects are also obtained from coal tar.

Coal Gas: Coal gas is mainly a mixture of hydrogen, methane and carbon monoxide. The gases present in coal gas are combustible and hence, it is an excellent fuel. It has high calorific value. It was used for lighting houses, factories and streets in Mumbai until 1950. It was also used for cooling earlier.

Coke: contains 98 % carbon. It is porous, tough, black and the purest form of coal. Like charcoal, it Is a good fuel and burns without smoke. It is largely employed as a reducing agent in the extraction of metals from their ores. It is also used in making fuel gases like water gas and producer gas.