If the volume of a gas, at constant temperature, changes from 200 ml to 500 ml, the pressure on the gas must have changed from 400 torr to .

160 torr

Explanation:

To calculate the new pressure, we use the equation given by Boyle's law. This law states that pressure is directly proportional to the volume of the gas at constant temperature.

The equation given by this law is:

where,

are initial pressure and volume.

are final pressure and volume.

We are given:

Putting values in above equation, we get:

Thus the pressure has changed to 160 torr

d.) the average kinetic energy of the gas particles is greater in container b because its particles move faster.