# How do you calculate vapor pressure?

## How do you calculate vapor pressure?

In chemistry, vapor pressure is the pressure that is exerted on the walls of a sealed container when a substance in it evaporates (converts to a gas). To find the vapor pressure at a given temperature, use the Clausius-Clapeyron equation: ln(P1/P2) = (ΔHvap/R)((1/T2) – (1/T1)).

What determines a molecule’s vapor pressure?

Types of Molecules: the types of molecules that make up a solid or liquid determine its vapor pressure. If the intermolecular forces between molecules are: relatively strong, the vapor pressure will be relatively low. relatively weak, the vapor pressure will be relatively high.

### How do you convert vapor pressure?

PV = nRT becomes n / V = P / RT, or pressure divided by the product of the universal gas constant and temperature. Convert the temperature into degrees Kelvin. Degrees Kelvin is equal to degrees Celsius plus 273.15. For example, 25 degrees Celsius equals 298 degrees Kelvin.

What is vapor pressure simple definition?

The vapor pressure is the force exerted on the walls of a closed container by the vaporized portion of a liquid.

## What factors affect vapor pressure?

Three common factors that influence vapor press are surface area, intermolecular forces and temperature. The vapor pressure of a molecule differs at different temperatures.

Can you have negative vapor pressure?

Because the azeotrope’s vapor pressure is higher than predicted by Raoult’s law, it boils at a temperature below that of either pure component. There are also systems with negative deviations that have vapor pressures that are lower than expected.

### What does high vapor pressure mean?

Vapor pressure is a property of a liquid based on the strength of its intermolecular forces. A liquid with weak intermolecular forces evaporates more easily and has a high vapor pressure. A liquid with stronger intermolecular forces does not evaporate easily and thus has a lower vapor pressure.