The gas used for inflating the tyres of aeroplanes is

Options

A. Ar
B. He
C. `H_(2)`
D. `N_(2)`

Explanation

To solve the question regarding the gas used for inflating the tyres of aeroplanes, we can follow these steps:

### Step 1: Understand the Options
The question provides four options for gases: Argon, Helium, Hydrogen, and Nitrogen. We need to evaluate each gas to determine which is suitable for inflating aeroplane tyres.

### Step 2: Evaluate Each Gas
1. **Argon**: This is an inert gas and is not typically used for inflating tyres due to its density and lack of reactivity.
2. **Helium**: While helium is a non-flammable gas and is lighter than air, it is not commonly used for inflating tyres because it is expensive and can escape quickly due to its small atomic size.
3. **Hydrogen**: Hydrogen is highly flammable and poses a significant risk in the event of a leak, making it unsuitable for tyre inflation.
4. **Nitrogen**: Nitrogen is a non-flammable, inert gas that is commonly used for inflating tyres. It helps maintain pressure and reduces the risk of oxidation and moisture inside the tyre.

### Step 3: Conclusion
Based on the evaluation, the gases that are suitable for inflating aeroplane tyres are **Helium** and **Nitrogen**. Therefore, the correct answers are Helium (option B) and Nitrogen (option D).

### Final Answer
The gases used for inflating the tyres of aeroplanes are **Helium and Nitrogen**.

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