Solid, liquid and gas
Everything around us is made of matter, and matter comes in three everyday states. A solid keeps its own shape, like an ice cube or a rock. A liquid flows and takes the shape of its container, like water in a glass. A gas spreads out to fill any space it is in, like the air around us or steam.
How matter changes state
Heating and cooling change matter from one state to another. Heat an ice cube and it melts into liquid water; heat the water more and it turns into a gas called water vapor; cool it down and it turns back again. It is the same stuff all along - its tiny particles are just moving faster or slower.
Frequently asked questions
What are the three states of matter?
The three everyday states of matter are solid, liquid and gas. A solid keeps its shape, a liquid flows and takes the shape of its container, and a gas spreads out to fill any space.
What makes matter change state?
Heating and cooling make matter change state. Adding heat makes the tiny particles move faster, turning a solid into a liquid and a liquid into a gas; taking heat away slows them down and reverses the change.
What is a solid, a liquid and a gas for kids?
A solid, like ice, keeps its shape. A liquid, like water, flows and takes the shape of whatever holds it. A gas, like steam, spreads out to fill all the space around it.