Which of the given statement is incorrect ?

Options

A. `He` is used in production of powerful super conducting magnets
B. `He` is used for carrying out experiments at low temperature as a cryogenic agent
C. `He` is used as an inert shield for arc welding
D. `He` is used in filling the gas balloons instead of `H_2` gas, because He is lighter than inflammable

Answer

To determine which of the given statements is incorrect, let's analyze each statement one by one.

1. **Statement 1: Helium is used in the production of powerful superconducting magnets.**
- Helium has the lowest melting and boiling points of any element, making it an ideal coolant for applications requiring extremely low temperatures, such as superconducting magnets. This statement is correct.

2. **Statement 2: Helium is used for carrying out experiments at low temperatures as a cryogenic agent.**
- Due to its low boiling point, helium is indeed used as a cryogenic agent in various experiments that require low temperatures. This statement is also correct.

3. **Statement 3: Helium is used as an inert shield for arc welding.**
- Helium is commonly used in welding processes as an inert gas to protect the weld area from atmospheric gases. This statement is correct as well.

4. **Statement 4: Helium is used in filling gas balloons instead of H2 gas because Helium is lighter than Hydrogen and non-inflammable.**
- This statement is incorrect. While helium is non-inflammable, hydrogen is actually lighter than helium. Therefore, the reason given in this statement is incorrect.

Based on the analysis, the incorrect statement is:

**Answer: Statement 4 is incorrect.**

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