Coke is obtained from :
Destructive distillation is the chemical process involving the decomposition of coal by heating to a high temperature in the absence of air. It is used for obtaining coke from coal.
Natural gas is a _____ resource :
Natural gas is a non renewable resource of energy. Natural gas is a kind of fossil fuel that take millions of years in its formation and cannot be reused again and again.
Gaseous mixture containing more volatile components of petroleum is called :
Natural gas is gaseous mixture containing more volatile components of petroleum. It is used in vehicle as compressed natural gas (CNG).
Fossil fuels are :
Dead remains of plants and animals are called fossils. Fossils used as source of energy are called fossil fuels. Fossil fuels are formed naturally.
A thick black liquid formed by heating coal in the absence of air :
Coal tar is a thick black liquid formed by heating coal in the absence of air. Coal tar is used to construct road and water proofing.
Coal is classified according to :
Different kinds of coal are found in earth crust. They are classified into different categories on basis of carbon content in it.
Such resources which can be continually replenished are called :
Natural resources are either exhaustible or inexhaustible. Those resources which can be continually replenished are called inexhaustible resources.
What is absent in coal ?
Coal mainly consists of carbon, hydrogen and oxygen besides sulphur. Phosphorus is absent in coal.
Coal type that contains lowest amount of carbon is :
Carbon content in lignite coal is less than 50%, so, lignite coal is the inferior quality of coal. Bituminous coal is best quality of coal.
Conversion of dead trees and other plants into coal is called :
Conversion of dead trees and other plants into coal inside the earth crust due to high temperature and pressure is called carbonisation.