Equilibrium between Phases of Matter Theory

Question 1

What is the equilibrium vapour pressure of a liquid?

Answer 1

The vapour pressure at the current temperature where the substance co-exists as both a vapour and a liquid.

The maximum pressure of a vapour that can exist in this volume at this temperature

Question 2

When is the equilibrium vapour pressure of liquid achieved?

Answer 2

When there are equal parts of the vapour condensing as are vaporizing in the liquid.

When the pressure of the vapour is equal to the external pressure of its surroundings

Question 3

What is humidity?

Answer 3

A messure of the partial pressure of the water vapour in the air.

[We use relative humidity as a messure for the pressure of water vapour currently in the air compared to how much pressure can be in the air (equilibrium vapour pressure of a liquid at the current temperature)]

Question 4

What is dew point?

Answer 4

The temperature where the partial pressure of the water vapour in the air is equal to the equilibirium vapour pressure of water at the current temperature.

The temperature when relative humidity is 100%