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Ideal Gas Equation


Boyle's Law: The law states that volume is inversely proportional to pressure.

Charles Law: This law states that volume is directly proportional to temperature.

Combined Gas Law: On combing both the laws we get volume is directly proportional to temperature/ pressure.

Avogadro's Law: According to this law, the volume is directly proportional to the number of moles.

Ideal Gas Equation 

From the above 3 laws we get:
  1. V=k.1/P
  2. V=k.T
  3. V=k.N
(k is a universal constant)

By combining all the 3 laws we get the gas law or the gas equation-

(P is pressure, V is volume, N is number of moles, R is universal constant and T is temperature)

Postulates of Ideal Gas 

There are some properties of an ideal gas given by scientist all over the world. These are:
  1. Gas particles behave as point masses.
  2. Particles posses Kinetic Energy.
  3. When particles strike the wall of the container, it is observed in the form of pressure.
  4. The collision between the particles is considered to be perfectly elastic i.e. no transfer of energy takes place.
  5. Interparticular space is very high so, there are no intermolecular forces of attraction. 
  6. The overall energy of the particles remains the same.
  7. The kinetic energy of particles increases with increase in temperature.

Any gas that follows the ideal gas equation is said to be an ideal gas. Any gas tends to behave as an ideal gas at a very low pressure and very high temperature.