Evaporation is also a state change from liquid to gas, but rather than being caused by heating, it is caused by the particles having random speeds spread over a distribution. There will be a small number of particles at any one point that are near the surface and are also moving fast enough that they can escape. Evaporation is therefore a slow process. As it takes away the fastest particles, evaporation will cool a liquid. Increasing a liquid’s temperature will increase the rate of evaporation.