The gaseous state is the simplest state of matter.

The periodic table contains only eleven elements that exist as gases.

The first reliable measurement of the properties of gases was made by Anglo-Irish scientist Robert Boyle .

The Gases are highly compressible.

Gases exert pressure equally in all directions.

Gases have a much lower density than the solids and liquids.

The volume and the shape of gases are not fixed.

Gases assume the volume and shape of the container.

Gases mix evenly and completely in all proportions without any mechanical aid.

The forces of interaction between the gas molecules are negligible.

The behaviour of gases is governed by some general laws, called gas laws

Gas laws are relationships between measurable properties of gases.

Measurable properties of gases are pressure, volume, temperature and mass .

The measurable properties describe the state of the gas.