Question

deeper into kinetic molecular theory review this graph of samples of gases at the same temperature. why do gases at the same temperature move at different average speeds? the greater the mass of the gas, the slower the average speed. the greater the intermolecular forces between the gas molecules, the greater the average speed. the greater the mass of the gas, the faster the average speed. the greater the intermolecular forces between the gas molecules, the slower the average speed.

Explanation:

According to kinetic - molecular theory, at the same temperature, the average kinetic energy of gas molecules is the same. Since kinetic energy $KE=\frac{1}{2}mv^{2}$, if the mass $m$ of a gas is greater, the speed $v$ must be lower to maintain the same kinetic energy. Intermolecular forces mainly affect the state and behavior of gases like condensation, not the average speed at a given temperature.

Answer:

The greater the mass of the gas, the slower the average speed.