Changing state
Definition:
Changing state of matter is the process in which a substance changes from one state (solid, liquid, gas) to another due to heating or cooling.
Main Details
Matter exists in three main states: solid, liquid, and gas.
Heating usually changes matter to a higher energy state:
Solid → Liquid (Melting)
Liquid → Gas (Evaporation/Boiling)
Cooling usually changes matter to a lower energy state:
Gas → Liquid (Condensation)
Liquid → Solid (Freezing)
Some substances can change directly from solid → gas (Sublimation) or gas → solid (Deposition).
Energy is absorbed when matter melts or evaporates and released when it freezes or condenses.
Examples:
Ice melting into water (solid → liquid)
Water boiling into steam (liquid → gas)
Dew forming on grass (gas → liquid)
Dry ice turning into carbon dioxide gas (solid → gas)
Fun Fact:
The energy needed to change the state of matter without changing its temperature is called latent heat.
Without changing state, water could never rise as steam to form clouds!