Select the order of increasing solubility of given gases in water at 293 K:
(A) $O_2 (K_H = 34.86\, kbar)$
(B) $He (K_H = 144.97\, kbar)$
(C) $N_2 (K_H = 76.48\, kbar)$
(D) $H_2 (K_H = 69.16\, kbar)$
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (B), (C), (D), (A)
The solubility of a gas in water is inversely proportional to its Henry’s law constant ($K_H$):
$\text{Solubility} ∝ \frac{1}{K_H}$
Given $K_H$ values (kbar):
- O₂ → 34.86 → highest solubility
- He → 144.97 → lowest solubility
- N₂ → 76.48
- H₂ → 69.16
Arrange in order of increasing solubility (lowest → highest):
$\text{He (B)} < \text{N₂ (C)} < \text{H₂ (D)} < \text{O₂ (A)}$
Answer: (B), (C), (D), (A)