Question

Pressure of the real gas is less than the pressure of ideal gas because:
A) No. of collisions increases
B) Definite shape of the molecule
C) K.E. of the molecule increases
D) Intermolecular forces

Answer 1

The gas which obeys all the gas laws under all types of temperature and pressure is termed as ideal gas while the gas which don’t obey the gas laws at low temperature and high pressure are termed as real gases.

Complete step by step answer:
In chemistry we deal with two types of gases, Ideal gases and Real gases. The gases which obey the gaseous laws at each and every temperature and pressure and have negligible volume are termed as ideal gases while the gases which didn’t obey the gaseous laws at every pressure and temperature value and have some volume are termed as real gases.
At low temperature and high pressure the real gases show deviation in their behavior but initially it was assumed that real gas also follows the ideal gas laws. In kinetic theory of gases we have some assumptions and one of them is that particles do not have attraction force between them, but it is not applicable for real gases. The particles of real gas have Van Der Waals attraction amongst them. The particles of Real gas show attraction with each other which provides a backward force to them and they can’t collide with the wall of the container with the same efficiency as they can collide without force of attraction between the particles. Hence the actual pressure which is applied by real gas is less than that of pressure applied on the walls of the container by ideal gas.
Hence we can conclude that due to intermolecular forces pressure of the real gas is less than the pressure of ideal gas.

So, the correct answer is Option D .

Note:
The forces of attraction or repulsion which occurs between the particles of a matter are known as intermolecular forces. These forces are weak attraction forces and mostly these are Van Der Waals forces of attraction which are weaker than ionic and covalent forces of attraction.