States of Matter

Everything around you is made of matter. Matter comes in different forms called states. The three main states are solid, liquid, and gas. Ice, water, and steam are all the same stuff in different states. Heat can change matter from one state to another.

Solids, Liquids, and Gases

A solid has its own shape and size, like a rock or a block of wood. A liquid takes the shape of its container, like water in a cup. A gas spreads out to fill any space, like air in a balloon. The tiny bits inside a solid are packed tight. In gases, they are far apart and move fast.

Changing States

Matter changes state when it gets hotter or colder. Ice melts into water when it warms up. Water boils into steam when it gets very hot. Steam turns back into water when it cools down. Water freezes into ice if it gets cold enough. These changes happen all the time in nature.

Fun Facts

• There is a fourth state of matter called plasma, which is found in stars.
• Water is one of the few things we see as a solid, liquid, and gas every day.
• Glass is a solid, but it has properties that make it a little like a liquid.

Did You Know?

The sun is mostly made of plasma, which is even hotter than a regular gas.