Question

From the molecular perspective, why is pressure directly proportional to temperature at fixed volume?

Answer 1

We know that, from kinetic molecular theory of gases, temperature is directly proportional to Kinetic energy of gases.

K.E T

SO, as the temperature increases, the K.E of gas molecules also increase which in turn increase the velocity of gas molecules. As the velocity of gas increases, collisions that occur among the gas molecules and with the walls of the container increases. The collisions with walls of the container nothing but pressure. So pressure of the gas will be increased as the temperature increases.