Question

Answer in Question 1: When temperature is increased, the heavy and light particles' (gas particles) kinetic energy is lower than when the temperature is higher.

Q5: If molecules are held in a container that is then opened to a second initially empty space, what do you expect to be true of the molecules making their way to that space?

Q6: Given the definition of temperature is the average kinetic energy of the molecules, what would your answer to question 1 suggest about the temperature in the newly opened space shortly after molecules have begun to enter it?

Answer 1

Question 5 Answer. There are two ways.

First gas is going slowly and gaining thermal energy from the temperature, they will use this energy as kinetic energy and use this in motion.

Second gas moves quickly that there is no time to gain heat from temperature of surrounding. In this case gas will use its internal energy and after the motion the temperature of gas would be decreased. (This situation is somewhat like tyre brust, air comes out from a higher pressure to lower pressure through small hole, so Joule's cooling effect.)

Question 6 Answer. The average kinetic of molecules is given by

KE = (1/2)k_BT where k_B is Boltzmann constant and T is temperature. (Here considering only translational kinetic energy).

The velocity of molecule is inversely proportional to square root of their mass.

v_rms = (3RT/M)^1\2 this is rms (root mean square) velocity,

In the first case the temperature of gas remains same, so, velocity remains same.

In second case temperature decreases, so, the velocity of the molecules also decrease.

So, from the velocity of the molecules we can say either temperature remained same or decreased.