- Evaporation is the process in which a liquid changes into a gas.
- Water on the ground or in the ocean heats up and evaporates, forming water vapor. The water vapor, or gas, rises into the atmosphere and is moved by the wind.
- Heat is the energy associated with the random motions of the molecules, atoms, or smaller structural units of which matter is composed. It is the form of energy arising from the motion of all the particles in a system. Energy is the power to cause change or to do work.
- Water vapor is still water, and it is a part of the air around you. Humidity is the amount of water vapor in the air.
- Gas is a state of matter that does not have a definite shape or volume. This means that gas changes both its shape and its volume very easily. Gas molecules do not hold together at all, so gas spreads out in all directions, including straight up.
- To boil is to change from a liquid state to a gas state by adding heat energy. So, when you heat water, the bubbles show how it is turning into gaseous vapor. This is the opposite of when water condenses.