Explain how compressing a gas affects its internal energy.

Compressing a gas increases its internal energy because work is done on the gas, transferring energy to the gas particles. This energy increase raises the average kinetic energy of the particles, which can lead to an increase in temperature.

Cause lens: Name the cause, then state the effect on particles, pressure, density, or energy. This question asks: Explain how compressing a gas affects its internal energy. The correct response is Compressing a gas increases its internal energy because work is done on the gas, transferring energy to the gas particles. This energy increase raises the average kinetic energy of the particles, which can lead to an increase in temperature., because gas pressure comes from particle collisions with container walls. In Increasing the pressure of a gas (physics only) (HT only), the marking point should connect directly to (Physics only) (HT only) Explain that compressing a gas can increase its internal energy. If the question includes values, the working must keep the appropriate unit and operation; if it is an explanation, it must name the relevant particle behaviour or energy change. This item belongs to Particle model and pressure, so avoid answers that switch to a different quantity, confuse heat with temperature, or describe gas pressure without collisions when collisions are the reason. Checkpoint 592 is distinct because it uses this exact question context and the cause lens rather than a generic particle-model sentence.