Question

What is the relationship between the vapour pressure and boiling point?

Answer 1

Vapour pressure:

The pressure of liquid-vapor on the surface of the liquid when equilibrium is established between the liquid and the vapor is called its vapor pressure.

Boiling point:

The temperature at which the vapor pressure of the liquid becomes equal to the external pressure and vaporization occurs throughout the liquid and vapors move freely in the surrounding is called its boiling point.

The relationship between vapor pressure and boiling point is described below:

1. The relationship between the vapour pressure and boiling point is that both are inversely proportional. The more volatile liquid evaporates fast as compared to the less volatile liquid at a low temperature because the volume increases with respect to temperature so it has a low boiling point.
2. For example, if acetone and water are placed at the same temperature in which acetone evaporates first because it has a low molecular force of attraction so it requires less heat to evaporate. Acetone has high vapor pressure and a low boiling point.