Gas laws are laws that explain the behaviour of an ideal gas. The following are some of the important gas laws:

## 1. Boyle’s Law:

Boyle’s law states that the volume of a given mass of gas (V) is inversely proportional to its absolute pressure (P), provided the temperature of the gas (T) remains constant.

According to Boyle’s law,

## 2. Charles’ Law:

According to Charles’ law, the volume of a given mass of gas (V) is directly proportional to its absolute temperature (T), when its pressure remains constant.

Mathematically,

## 3. Amontons’ law (or Gay-Lussac’s Law):

Amontons’ law states that if the volume of a given mass of a gas (V) is kept constant, then the pressure of the gas (P) is directly proportional to its absolute temperature (T).

According to this law,

## 4. Joule’s Law of Internal Energy:

Joule’s law of internal energy states that the internal energy of a given quantity of gas depends only on its temperature and is independent of its pressure and volume.

i.e, ΔU ∝ T

where ΔU → Change in internal energy

## 5. Regnault’s Law:

Regnault’s law states that the specific heat capacity of a gas at constant pressure (C_{p}) and the specific heat capacity of a gas at constant volume (C_{v}) do not change with change in pressure and temperature. According to this law, C_{p} and C_{v} values of a gas remain constant.

## 6. Avogadro’s Law:

This law states that equal volumes of different perfect gases, at the same temperature and pressure, contain equal number of molecules.

According to Avogadro’s law,

where,

V → Volume of gas

n → Amount of substance of the gas