Question

Gas exerts pressure on the walls of the container because gas:
(A). Has weight
(B). Molecules have momentum
(C). Molecules collide with each other
(D). Molecules collide with the wall of the containers

Answer 1

- Hint: Gases have a very low (negligible) value of intermolecular force of attraction between the particles. Thus they have motion in all the directions randomly. Also firstly we will define the force of attraction between the molecules.

Complete step-by-step solution -
There are two force of between the molecules of gas attraction and repulsion
Intermolecular force of attraction is the attractive force between the molecules which keep the molecules together.
Thus due to weaker molecular force of attraction these molecules are continuously colliding with each other and also with the wall of container exerting force and pressure exerted by it is the sum of all these collision forces of the container. The more particles will hit the container more will be forced exerted hence more pressure will be there. Also they bounced back in all directions randomly due to which there is equal pressure at all the points of the container.
The pressure of any gas can be calculated using the following formula:
$
  PV = nRT \\
  P = \dfrac{{nRT}}{V} \\
$
Where
$P = $ Pressure exerted on the gas
$V = $ Volume of the container
$n = $ Amount of gas (moles)
$R = $ Constant
$T = $ Temperature in Kelvin.

From the above equation it is clear that pressure can be increased in three ways:-
On increasing temperature.
On increasing the amount of gas.
By decreasing the volume of the container.
Hence the correct option is D.

Note- Gas exerts more pressure than liquid on the wall of the container in which they are kept because they have less intermolecular force than liquid.The pressure exerted by the gas is due to the spontaneous movement of the ions in the air. Gasses have weak intermolecular forces and particles in continuous random motion, and these particles collide with the walls. And therefore brought pressure on the gas.