A sample of gas has increased in temperature from 20° Celsius to 22° Celsius. Which of the following happens as the temperature of the gas goes up?

The gas undergoes a phase change.

The velocity of the gas particles decreases.

The kinetic energy of the particles increases.

An exothermic reaction is more likely to occur.

The correct answer for this question is the statement 'the kinetic energy of the particles increases'. As the temperature of gas goes up, the kinetic energy of the particles increases because their velocities increase. This is because particles get excited and hit each other more - leading to increase in kinetic energy.