The gas used for inflating the tyres of aeroplanes: This question has multiple correct options.

(A)- Ar

(B)- He

(c) - H₂

(d) -N₂

In the tyres, they have small pores through which the air present inside leaks out naturally with time. As they are often subjected to variation in temperature, an air-filled tyre may under high temperature and pressure expands and may cause explosion or may contract into ice at low temperature and pressure.

So, an inert gas like nitrogen is used which is chemically unreactive to the rubber, as it blocks the oxidation of rubber which may make it brittle. And due to the size of its molecules more than the air molecules it does not leak out easily. Therefore, maintaining optimum pressure within the tyres for a longer period and saving the amount of fuel.

The oxygen, water, and other gases are sucked out of the tyre by continuous filling and purging several times. So, due to less moisture present inside the tyres in the presence of nitrogen, they get less corroded.

The tyre wear is slower in a properly inflated tyre. It is a good alternative both economically and environmentally. As seen, a consistent inflation pressure, increases the tyre life, good mileage, better fuel economy and less emission of harmful gases in nature and also decreases in the manufacture of tyres. The helium gas is also non-inflammable and inert like nitrogen.

So, the correct answer is “Option B and D”.