The gas used for inflating the tyres of aeroplanes:

This question has multiple correct options.

(A)- Ar

(B)- He

(C)- H2

(D)- N2

When it comes to inflating the tires of airplanes, the choice of gas is crucial for safety and performance. The options you've provided—argon (Ar), helium (He), hydrogen (H2), and nitrogen (N2)—each have their own properties, but only certain ones are commonly used in aviation. Let's break down each option to see which gases are suitable for this application.

Understanding the Properties of Each Gas

Nitrogen (N2)

Nitrogen is the most widely used gas for inflating aircraft tires. Here’s why:

• Inert Nature: Nitrogen is an inert gas, meaning it does not react easily with other substances. This property minimizes the risk of chemical reactions that could lead to tire degradation.
• Pressure Stability: Nitrogen maintains tire pressure better than air, as it is less likely to leak through the tire material. This is crucial for maintaining optimal performance during flights.
• Reduced Oxidation: Using nitrogen helps reduce oxidation inside the tire, which can extend the lifespan of the tire and improve safety.

Helium (He)

Helium is not typically used for inflating airplane tires, but it has some interesting properties:

• Lightweight: Helium is much lighter than air, which could theoretically reduce the overall weight of the aircraft.
• Non-flammable: Like nitrogen, helium is non-flammable, making it safe in terms of fire risk.

However, helium is not practical for tire inflation due to its high cost and the fact that it can escape from tires more quickly than nitrogen.

Hydrogen (H2)

Hydrogen is generally avoided for inflating tires due to its flammability:

• Highly Flammable: Hydrogen poses a significant fire risk, especially in the high-temperature environment of an aircraft tire during takeoff and landing.
• Storage Challenges: Hydrogen requires special storage conditions and handling procedures, making it impractical for routine use in aviation.

Argon (Ar)

Argon is another inert gas, but it is rarely used in aviation tire inflation:

• Cost: Argon is more expensive than nitrogen and does not offer significant advantages that would justify its use in tires.
• Availability: Nitrogen is more readily available and easier to source for aviation needs.

Final Thoughts

Given the analysis of these gases, the most suitable option for inflating airplane tires is nitrogen (N2). It provides the necessary stability, safety, and performance required for aviation. While helium and argon have their own unique properties, they do not meet the practical needs of aircraft tire inflation. Hydrogen, due to its flammability, is not a viable option at all. Therefore, the correct answer to your question is (D) N2.