How does an increase in temperature generally affect the speed of gas molecules?

An increase in temperature generally causes the speed of gas molecules to increase due to the relationship defined by the kinetic molecular theory of gases. According to this theory, temperature is a measure of the average kinetic energy of the gas molecules. When the temperature rises, the kinetic energy of the molecules increases, leading to more vigorous motion. As a result, gas molecules move faster as they gain energy from the heat applied to them.

This increase in speed contributes to the behavior of gases, such as the expansion of gas when heated or an increase in pressure within a closed container. The relationship between temperature and molecular speed is directly proportional—higher temperatures lead to increased speeds, while lower temperatures result in decreased speeds. Thus, the correct understanding aligns with the assertion that the speed of gas molecules increases with a rise in temperature.