Henry's law describes the relationship between which quantities?

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Multiple Choice

Henry's law describes the relationship between which quantities?

Henry's law states that at a fixed temperature, the amount of a gas that dissolves in a liquid is proportional to the partial pressure of that gas above the liquid. In mathematical terms, the concentration of dissolved gas equals Henry's constant times the gas pressure (C = kH × Pgas). This means higher pressure pushes more gas into solution, and if you reduce the pressure, dissolved gas decreases and can come out of solution. The constant kH depends on the specific gas–solvent pair and the temperature. This concept is familiar in carbonated beverages, where increasing pressure dissolves more CO2, and releasing the cap lowers the pressure so CO2 escapes. It’s important to remember that Henry’s law assumes constant temperature and relatively low concentrations where the relationship remains linear. Why the other ideas don’t fit: changing temperature affects solubility but isn’t the direct pressure–concentration relationship described by Henry’s law; the rate at which gas dissolves concerns kinetics rather than equilibrium solubility; and the volume–temperature relationship refers to the ideal gas law, not dissolution of a gas in a liquid.

Henry's law states that at a fixed temperature, the amount of a gas that dissolves in a liquid is proportional to the partial pressure of that gas above the liquid. In mathematical terms, the concentration of dissolved gas equals Henry's constant times the gas pressure (C = kH × Pgas). This means higher pressure pushes more gas into solution, and if you reduce the pressure, dissolved gas decreases and can come out of solution. The constant kH depends on the specific gas–solvent pair and the temperature.

This concept is familiar in carbonated beverages, where increasing pressure dissolves more CO2, and releasing the cap lowers the pressure so CO2 escapes. It’s important to remember that Henry’s law assumes constant temperature and relatively low concentrations where the relationship remains linear.

Why the other ideas don’t fit: changing temperature affects solubility but isn’t the direct pressure–concentration relationship described by Henry’s law; the rate at which gas dissolves concerns kinetics rather than equilibrium solubility; and the volume–temperature relationship refers to the ideal gas law, not dissolution of a gas in a liquid.

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