# Vapor Pressure Formula

## Vapour Pressure Formula

Vapour Pressure Formula is defined as the pressure created by the vapour of a liquid (or solid) on its surface. This pressure is formed in a closed container at a specific temperature while in a thermodynamic equilibrium state. The equilibrium vapour pressure determines the rate of evaporation of a liquid. Vapour Pressure Formula rises as temperature rises. The boiling point of a liquid is the point at which the pressure exerted by the surrounding environment equals the pressure exerted by the vapour.

Some of the characteristics of the Vapour Pressure Formula are

1. In comparison to a liquid’s solution, a pure liquid has a higher vapour pressure.
2. It is inversely proportional to the forces of attraction that exist between liquid molecules.
3. Vapour Pressure Formula increases as the temperature rises. This is due to the molecules gaining kinetic energy and rapidly vaporising.

What is the Vapour Pressure Formula?

When a solid dissolves in a liquid, a solution is formed. The addition of the solute lowers the vapour pressure formed by this solution. Mentioned below is the Vapour Pressure Formula using Raoult’s law, which explains how the addition of a solute changes the vapour pressure of a liquid.

P solution = (X solvent)(Po solvent)

X solvent = the solvent mole fraction in the solution

P solution = the solution’s vapour pressure

P°solvent = the solvent’s vapour pressure

### Solved Examples

To learn more about Vapour Pressure Formula and find solutions to all the questions related to the topic, students can refer to the various study resources offered by Extramarks. Extramarks provides various resources such as NCERT solutions, Revision notes, Past years’ papers solutions, etc for the benefit of students. Extramarks provides study materials for students of Class 1 to Class 2. Students can rely on the resources offered as they are written by expert subject teachers. Further, these resources are written and updated regularly according to the latest CBSE guidelines and NCERT recommendations. Moreover, Extramarks provides all the resources in both Hindi medium and English medium. The resources offered by Extramarks can be downloaded from the website and mobile application in PDF format. Students must download the resources to enhance their scores and improve their knowledge.