Q.When a gas is heated its temperature increases. Explain this phenomenon based on the kinetic theory of gases.

[!TLDR] Heating raises average molecular kinetic energy, and since KE ∝ T, temperature rises. [!ANSWER] Heating increases the average kinetic energy of the gas molecules, and since temperature is a direct measure of that average kinetic energy, the temperature rises.

According to kinetic theory, the average translational kinetic energy of a gas molecule is directly proportional to the absolute temperature of the gas: (1/2) m <v^2> = (3/2) kB T. When heat is supplied to a gas, that energy goes into increasing the kinetic energy of the constantly, randomly moving molecules -- their speeds, on average, increase. Because average molecular kinetic energy IS, by this kinetic-theory relation, what temperature physically represents, an increase in average kinetic energy is exactly the same thing as an increase in temperature. There is no separate 'temperature mechanism' apart from this -- heating a gas simply means increasing the vigour of its molecules' random motion, and that increased vigour is registered macroscopically as a higher temperature. [!ANSWER] Heating increases the average kinetic energy of the gas molecules, and since temperature is a direct measure of that average kinetic energy, the temperature rises.

Apply the kinetic-theory relation between average molecular kinetic energy and absolute temperature, (3/2)kBT, to explain heating as a rise in molecular KE.

Describing heating and rising temperature as two separate, merely correlated effects, rather than recognising that kinetic theory identifies temperature AS a direct measure of average molecular kinetic energy.