Question

Which of the following fuels causes minimum environmental pollution?
A. Hydrogen
B. Coal
C. Diesel
D. Kerosene

Answer 1

Hint: The various gases in the atmosphere can be both good and bad. Some of them are harmless while some can even lead to fatal conditions even present in excess. Every gas or vapour has a certain concentration until it is bearable and non-toxic but when it exceeds a certain range, it becomes fatal.

Complete answer:
Burning of various organic matter releases the carbon dioxide in the air causing the pollution. Pollution is the addition of unwanted and non-useful particles in the air or water.
Option A: Hydrogen: Hydrogen on burning will form the water vapours. They are not harmful to any of the organic things so they do not cause pollution.
Option B: Coal: Coal on burning comes in contact with oxygen, the chemical energy is converted into thermal energy that is heated. But it also gives carbon dioxide and methane in the environment.
Option C: Diesel: The petroleum fuels burn to give carbon dioxide, water and nitrogen. Combustion of fuel gives these harmful gases which when released into the environment will pollute it.
Option D: Kerosene: It is the combustible hydrocarbon derived from petroleum, a fuel. So it will also give carbon dioxide and nitrogen to pollute the environment.

So the answer is option A: Hydrogen.

Note: Carbon dioxide, carbon monoxide and methane are harmful to the environment as well as life existing on Earth. Their high exposure causes suffocation, dizziness, weakness, loss of coordination etc. Carbon dioxide is the greenhouse gas which will lead to increased temperature on the Earth.