Question

At 293 K, methane gas was passed into 1 L of water. The partial pressure of methane is 1 bar. The number of moles of methane dissolved in 1 L water is
(K$_H$ of methane = 0.4 kbar).

• A. \( 1.38 \)
• B. \( 1.38 \times 10^{-2} \)
• C. \( 1.38 \times 10^{-3} \)
• D. \( 1.38 \times 10^{-1} \)

Hint:

Henry’s law helps determine gas solubility in liquids. A higher Henry’s constant means lower solubility.

Answer 1

The Correct Option is D

Step 1: Use Henry’s law. Henry’s law states: \[ C = \frac{P}{K_H} \] where \( C \) is the concentration, \( P \) is the pressure, and \( K_H \) is the Henry’s law constant. 

Step 2: Substitute the values. \[ C = \frac{1}{0.4} = 1.38 \times 10^{-1} \text{ mol/L} \]