Henry’s law

Definition

Henry's law states that the solubility of a gas in a liquid is directly proportional to the partial pressure of that gas above the liquid. This relationship is typically expressed as $C = kP$, where $C$ is the concentration of the gas, $k$ is Henry's law constant, and $P$ is the partial pressure.

5 Must Know Facts For Your Next Test

1. Henry's law applies primarily to dilute solutions of gases in liquids.
2. The value of Henry's law constant ($k$) varies with temperature and the nature of both the solute (gas) and solvent (liquid).
3. Higher temperatures generally decrease the solubility of gases in liquids according to Henry's law.
4. Real gases deviate from Henry’s law at high pressures or low temperatures due to non-ideal behavior.
5. Henry’s law is important in various applications, such as calculating dissolved oxygen in water or carbon dioxide in carbonated beverages.

Review Questions

• What does Henry's law state about the relationship between gas solubility and partial pressure?
• How does temperature affect Henry's law constant ($k$) and gas solubility?
• Why do real gases deviate from Henry’s law under certain conditions?

Related terms

Partial Pressure:

The pressure exerted by a single component of a mixture of gases.

Solubility:

The ability of a substance to dissolve in a solvent to form a homogeneous solution.

Raoult's Law:

A principle stating that the vapor pressure of an ideal solution is dependent on the vapor pressure of each chemical component and their respective mole fractions.