Question

According to Henry’s Law, in gases, an increase in pressure increases:

• A. Solubility
• B. Saturation
• C. Volume
• D. Viscosity

Hint:

When pressure increases, the gas molecules are forced into the solution, leading to higher solubility.

Answer 1

The Correct Option is A

According to Henry’s Law, in gases, an increase in pressure increases: 

• Option 1: Solubility - This is the correct answer. Henry's Law states that the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid. When the pressure increases, more gas dissolves into the liquid.
• Option 2: Saturation - While increasing pressure can lead to a more saturated solution, Henry’s Law specifically deals with the solubility of gases, not saturation.
• Option 3: Volume - This is incorrect because the volume of a gas decreases with an increase in pressure (according to Boyle’s Law), not its solubility.
• Option 4: Viscosity - This is unrelated to Henry’s Law. Viscosity is the measure of a liquid’s resistance to flow, and it does not directly relate to pressure in the context of Henry’s Law.

Explanation:

Henry’s Law states that for a gas dissolved in a liquid at a constant temperature, the amount of gas that dissolves is directly proportional to the partial pressure of the gas above the liquid. So, as the pressure of the gas increases, the solubility of the gas in the liquid also increases.

Answer 2

Henry's law can be written as an equation, p = KH x, where p is the partial pressure of the gas above the liquid, KH is Henry's constant for that gas-liquid pair at a given temperature, and x is the mole fraction of the dissolved gas, which is a direct measure of its solubility. Rearranging gives x = p / KH. Let's check each option against this equation.

1. Solubility: Since x = p / KH and KH stays fixed at constant temperature, raising p directly raises x. So solubility grows in step with pressure, matching the equation.
2. Saturation: Saturation describes the state where a solution holds the maximum solute it can at given conditions, but Henry's equation talks about the amount dissolved, not about reaching a saturation point, so it is not what the equation predicts.
3. Volume: Henry's law equation has no volume term in it at all, so pressure changing cannot be read off this equation as changing volume.
4. Viscosity: Viscosity also does not appear anywhere in the p = KH x relation, so the equation gives no basis for pressure affecting viscosity.

Only solubility appears as a variable that scales directly with pressure in Henry's law.

So the correct answer is Solubility.