22 September 2014

Natural Gases : Science Ncert

Natural Gases : Science Ncert / Cbse Revision Notes

Natural gas is another fossil fuel, like coal and petroleum. It is a non-renewable fuel. Natural gas is used for waste treatment and incineration. Gases like butane, ethane and propane may be extracted from it and used as feedstock for products such as fertilisers and pharmaceutical products
Natural gas is one of the most useful, clean and safe energy sources. It is a colourless and odourless gas in its pure form and is made up of many gases of which methane is the most prominent. The chemical formula for methane is CH4.

What is a Natural Gas? , Cbse / Ncert Revision Notes, Uses of Natural Gases

When natural gas burns, it gives off a great deal of energy, and unlike other fossil fuels, leaves no ash.  It causes very little air pollution, as methane burns almost completely. 
It is one of the cleanest burning fuels and produces mostly heat, carbon dioxide and water vapour.  Thus, it is said that it contributes to a cleaner and greener environment.

Natural gas is odourless. To detect gas leaks, a harmless but pungent odorant that smells like rotten eggs is added to it, as a safety measure. It can be smelt in case of even a small leak. When natural gas is mixed with the correct amount of air and ignited, this colourless, invisible gas burns with a clean, blue flame.
Natural gas is measured in British Thermal Units (BTU). About 2,500 years ago, the Chinese discovered that natural gas could be burned. They used bamboo to pipe it from shallow wells and burned it to boil seawater. This way they made water drinkable and separated the salt.

Must Read : Natural Resources

Uses of natural gas:

  • For cooking.
  • To run central heating and cooling systems, and cloth dryers.
  • For electricity generation through the use of gas turbines and steam turbines.
  • In the manufacture of fabrics, glass, steel, plastics, paint and other products.

Natural gas is compressed to a high pressure and stored in hard cylindrical or spherical containers, for distribution. It is then known as Compressed Natural Gas or CNG.
CNG is also distributed to homes and industries through pipes, For example, in India, such a network of pipelines exists in Vadodara in Gujarat and some parts of Delhi. CNG is now used as a fuel for transport vehicles – from light duty trucks, auto rickshaws and taxi cabs to delivery vans and heavy duty vehicles like buses.