Correct Option
The correct option is p = KH x.
Explanation
Henry’s Law governs the solubility of a gas in a liquid at a constant temperature. It establishes a quantitative relationship between the pressure of the gas above the liquid surface and the amount of gas dissolved in the liquid.
Analysis
According to Henry’s Law, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas present above the surface of the liquid or solution. The most common mathematical representation uses the mole fraction to measure solubility:
- Statement: The partial pressure of the gas in the vapour phase (p) is proportional to the mole fraction of the gas (x) in the solution.
- Formula: This proportionality is expressed as:
p = KH · x - Components:
- p = Partial pressure of the gas
- x = Mole fraction of the gas in the solution
- KH = Henry’s law constant (depends on the nature of the gas, solvent, and temperature)
Comparison with other options:
- p = p0 x (p = p0 x) represents Raoult’s Law for liquid-liquid solutions, where p0 is the vapour pressure of the pure component.
- Options x = p0 / p and x = Kb p do not represent standard thermodynamic relations for gas solubility.
Key Takeaway: Henry’s Law is mathematically defined as p = KH x, indicating that higher partial pressure leads to higher solubility (mole fraction) of the gas in the liquid.