vapor pressure

Thân thiện

The water in the beaker has a measurable vapor pressure.

Definition

1. Noun:
   • The pressure exerted by a vapor: This is the pressure a vapor exerts when it is in equilibrium with its own liquid or solid phase, or when it is confined in a closed container.
   • Saturated vapor pressure: Often, the term specifically refers to the maximum pressure a vapor can exert at a given temperature when it is in equilibrium with its liquid (or solid) form.

Usage

• Vapor pressure is a key concept in physical chemistry and thermodynamics.
• It is used to describe the volatility of a liquid; a higher vapor pressure indicates a more volatile liquid.
• It explains phenomena like evaporation, boiling, and the behavior of gases in closed systems.

Examples

• Noun:
  • The vapor pressure of water at 100°C is equal to atmospheric pressure, which is why it boils.
  • A volatile solvent like diethyl ether has a high vapor pressure at room temperature.
  • Meteorologists consider the vapor pressure of water in the air when calculating humidity.

Advanced Usage

• "Equilibrium vapor pressure": Another term for saturated vapor pressure, emphasizing the state of dynamic equilibrium between evaporation and condensation.
  • The equilibrium vapor pressure is dependent only on the substance and its temperature.
• "Partial vapor pressure": In a mixture of gases, this is the contribution to the total pressure from a specific vapor.
  • Dalton's Law states that the total pressure is the sum of the partial vapor pressures of each component gas.

Variants and Related Words

• Saturation pressure: A synonym for saturated vapor pressure.
• Vapour pressure: The British English spelling.
• Evaporation: The process by which a liquid turns into a vapor, closely related to vapor pressure.

Synonyms

• Saturated vapor pressure (specific meaning)
• Equilibrium vapor pressure

Related Scientific Contexts

• Boiling point: The temperature at which a liquid's vapor pressure equals the surrounding atmospheric pressure.
• Raoult's Law: A law of thermodynamics stating that the partial vapor pressure of a component in a mixture is equal to the vapor pressure of the pure component multiplied by its mole fraction in the mixture.
• Clausius-Clapeyron equation: Describes the relationship between vapor pressure and temperature for a substance.

Học thuật

Noun

1. the pressure exerted by a vapor; often understood to mean saturated vapor pressure (the vapor pressure of a vapor in contact with its liquid form)

Từ đồng nghĩa

• vapour pressure