Question

In water, which of the following gases has the highest Henry’s law constant at 293 K?

• A. N2
• B. O2
• C. He
• D. H2

Hint:

For gases, the higher the Henry's law constant, the less soluble the gas is in the solvent.

Answer 1

The Correct Option is C

Henry's law states that the amount of gas that dissolves in a liquid is proportional to the partial pressure of the gas above the liquid, expressed as: \[ C = k_H \cdot P \] Where: - \(C\) is the concentration of the gas in the liquid,
- \(k_H\) is the Henry’s law constant,
- \(P\) is the partial pressure of the gas.
For gases dissolved in water, the Henry’s law constant is inversely proportional to the solubility of the gas in water. A higher Henry's law constant indicates that the gas is less soluble in water.
Among the given gases, helium (\(\text{He}\)) has the highest Henry’s law constant because it is less soluble in water compared to the other gases listed (like \(\text{N}_2\), \(\text{O}_2\), and \(\text{H}_2\)).
Therefore, the correct answer is helium (\(\text{He}\)).