What is the Difference Between Vapor Pressure and Partial Pressure?

The main difference between vapor pressure and partial pressure lies in the substates of matter they refer to.

Vapor Pressure refers to the pressure exerted by the vapor (gas phase) in its thermodynamic equilibrium with its condensed state of liquid. It is a measure of the tendency of a material to change from a liquid or solid to a gas. Some key points about vapor pressure include:

1. Vapor pressure is applicable only to the solid and liquid phases.
2. It does not depend on the surface area or the system's volume.
3. Vapor pressure can be calculated using the solute's mole fraction.

Partial Pressure is the pressure exerted by an individual gas in a mixture as if it were alone in that system. According to Dalton's Law, the total pressure of an ideal gas mixture is the sum of the partial pressures of the gases in the mixture. Some key points about partial pressure include:

1. Partial pressure is applicable only to the gaseous phase.
2. It can be calculated using the gas's mole fraction.
3. Each constituent gas in a mixture has a partial pressure, which is the notional pressure of that gas if it were alone in the system.

In summary, vapor pressure is the pressure exerted by a vapor in equilibrium with its liquid or solid phase, while partial pressure is the pressure exerted by an individual gas in a mixture as if it were alone in the system.

Comparative Table: Vapor Pressure vs Partial Pressure

Here is a table summarizing the differences between vapor pressure and partial pressure:

Vapor pressure is the pressure exerted by the vapor of a substance in equilibrium with its liquid or solid phase, and it is specific to liquids and solids. On the other hand, partial pressure is the pressure exerted by an individual gas in a mixture of gases, and it is applied to gaseous phases only. In any given mixture, each gas component has its own partial pressure, which is independent of other gases.