Three States of Matter

States of Matter for Kids

This lesson is about states of matter for kids. Learn facts about states of matter.

Matter is all around us. All materials that we know can be grouped as solids, liquids and gases.

Examples of matter around us

These groups are called the three states of matter.

Examples of three states of matter

Wood ➡ Solid
Water ➡ Liquid
Air ➡ mixture of gases

Most of the substances on Earth are solids at everyday temperatures. Therefore, only a few substances are liquids or gases compared to the amount of solids.

Properties of solids liquids and gases
Properties of Solids	Properties of Liquids	Properties of Gases
Definite shape (A solid can be cut or shaped only when an external force acts upon it. E.g. You can carve a piece of wood into a sculpture You can stretch or bend rubber without breaking Metal and plastic can be melted and can change the shape when cools down) The properties of many solids make them useful materials for manufacturing items.	Indefinite shape (A liquid takes the shape of the container which it is kept) Put the same volume of water into each container. You can see how water takes the shape of the different containers it’s put into.	Indefinite shape (A gas spreads all over the place to fill up the space which it is kept)
Definite volume	Definite volume	Indefinite volume
Highest density	Density is lower than solid	Lowest density
Rigid and cannot flow	Can flow. Flows to the lowest point that it can, so that it fills the bottom part of a container. Can flow
Greatest force of attraction among particles	Less force of attraction among particles compared to solids	Least force of attraction among particles
Particles are tightly packed and cannot move freely.	Particles are loosely packed compared to solids and can move freely by sliding over one another.	Particles are very loosely packed. The particles are in a continuous random motion because the gaps among particles are the greatest.
Cannot be easily compressed (squashed), expanded or changed	Cannot be compressed (squashed)	Can be easily compressed (squashed)

Due to the property fluidity, gases and liquids are called fluids, because they both can flow.

Plasma

Plasma is the fourth state of matter. It rarely exists naturally on Earth. We’ll later discuss about the state plasma.

Solid to liquid to gas

We identify substances as solids, liquids and gases in everyday conditions. This normal condition is often at the room temperature, which is the temperature inside a building and under normal atmospheric pressure. Various substances can exist in all three states of matter. The best example is water.

Three states of water

Water can be a solid ➡ Ice
Water can be a liquid ➡ Water
Water can be a gas ➡ Water vapour or steam

Learn how materials change their state with this lesson, states of matter for kids.

Changing States

Materials can be changed from one state to another by heating or cooling (freezing). When a substance changes from one state to another a change of state happens.

The most common substance, water as an example;

Freezing Water and Melting ice

Heating Water and Cooling Water Vapour

Hope you’ve enjoyed the lesson states of matter for kids. Also, try the activities ‘Solid, Liquid and Gas‘ and ‘States of Matter Quiz‘

Written By : K8School