Solids, Liquids and Gases
The World of Solids, Liquids and Gases
Items in this lesson
The World of Solids, Liquids and Gases
What do you already know about solids, liquids, and gases?
Learning Objective
At the end of the lesson you will be able to name and describe solids, liquids, and gases, and explain how their particles move.
What Are Solids, Liquids and Gases?
Matter around us can be a solid, a liquid, or a gas. These are called the three states of matter.
What is a Solid?
A solid keeps its shape. The particles in a solid are packed tightly together and do not move around easily.
What is a Liquid?
A liquid takes the shape of its container. Its particles are close, but they can slide over each other.
What is a Gas?
A gas spreads out to fill the space it is in. Its particles move freely and are far apart.
How Do Particles Move?
Solids
Particles vibrate in place, they do not move past each other.
Particles in liquids move around each other, while in gases, they move quickly in all directions.
Liquids & Gases
Solid, Liquid or Gas?
Look at objects around you. Can you find one solid, one liquid and one gas in your home or classroom?
Changing State
Solids can turn to liquids when heated (melting). Liquids can become gases (evaporation). Gases can become liquids when cooled (condensation).
Melting and Freezing
When ice gets warm, it melts to become water. When water gets cold, it freezes to become ice.
Evaporation
When water is heated, it changes into steam, which is a gas.
Condensation
When warm air meets something cold, water droplets can form. This is called condensation.
What Have You Learned?
Name a solid, a liquid, and a gas that you use every day. Can you explain how their particles move?
Write down 3 things you learned in this lesson.
Write down 2 things you want to know more about.
Ask 1 question about something you haven't quite understood yet.
