Which one of the following statements regarding helium is
incorrect ?

Options

A. It is used to produce and sustain powerful superconducting
magnets
B. It is used as a cryogenic agent for carrying out experiments at low temperature
C. It is used in filling balloons for meterological observations
because it is lighter and non-inflammable
D. It is used as diluent for oxygen in modern diving apparatus
because of its high solubility in blood

Explanation

To determine which statement regarding helium is incorrect, we will analyze each statement provided about helium.

### Step-by-Step Solution:

1. **Statement 1: "It is used to produce and sustain powerful superconducting magnets."**
- Helium is indeed used in the production and maintenance of superconducting magnets due to its very low boiling point (4.2 K). This allows it to remain in a liquid state at very low temperatures, which is essential for superconductivity.
- **Conclusion:** This statement is correct.

2. **Statement 2: "It is used as the cryogenic agent for carrying out experiments at low temperatures."**
- Helium is widely used as a cryogenic agent because of its low boiling point. It effectively cools materials to very low temperatures, making it suitable for various scientific experiments.
- **Conclusion:** This statement is correct.

3. **Statement 3: "It is used in filling balloons for meteorological observations because it is lighter and non-inflammable."**
- Helium is indeed used to fill balloons for meteorological purposes. It is lighter than air and does not catch fire, making it a safer alternative to hydrogen.
- **Conclusion:** This statement is correct.

4. **Statement 4: "It is used as the diluent for oxygen in modern diving apparatus because of its high solubility."**
- While helium is used as a diluent for oxygen in diving mixtures, the reason given is incorrect. Helium has low solubility in blood, which is why it is preferred over nitrogen in deep-sea diving. The low solubility helps prevent decompression sickness (the bends).
- **Conclusion:** This statement is incorrect because it states "high solubility" instead of "low solubility."

### Final Answer:
The incorrect statement regarding helium is **Statement 4**: "It is used as the diluent for oxygen in modern diving apparatus because of its high solubility."

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