Living on Earth: Matter and Materials

What everything is made of

Everything around us is matter, and all matter is made of tiny particles. How those particles are arranged decides whether something is a solid, a liquid or a gas, and how it behaves. Matter also comes in different kinds: elements, made of one type of atom; compounds, where elements are chemically joined; and mixtures, where substances are simply together. And the materials we build with are chosen for their properties. This module covers the particle model, the kinds of matter, and how we pick a material for a job.

Matter words to know

Learn these before you study any material. They name the building blocks of matter and the qualities that decide how a material is used.

Match the state to how its particles behave

An element against a compound

Both are pure substances, but they are not the same. The difference is whether more than one kind of atom is joined together.

Element, compound or mixture?

A substance is made of two different elements chemically joined together, and it has different properties from either element on its own. What is it?

• A compound
• An element
• A mixture
• A single atom

Choose a material for the job

Materials are chosen for their properties, not by habit. Ask what the object must do: carry a load, conduct heat, resist water, or stay light. Then pick a material whose properties match. A metal conducts heat and is strong; a plastic is light and resists water. Name the property, name the need, and show that they match: that is how a scientist justifies a choice of material.

Pick the properties of a metal

Select every statement that is generally true of metals.

• They conduct electricity well
• They conduct heat well
• They are usually strong
• They are always liquids
• They never conduct electricity

Order the changes of state

A solid is heated steadily until it becomes a gas. Put the stages in order.

• A solid, with particles packed and vibrating
• It melts as the particles gain energy
• A liquid, with particles close but moving
• It boils as the particles gain more energy
• A gas, with particles far apart and fast

Complete the matter facts

A substance made of only one kind of atom is an _____. Two or more elements chemically joined is a _____. Substances together but not joined make a _____. The amount of mass in a certain volume is the _____.

One material, chosen on purpose

Think about why a saucepan is made of the materials it is. The body is metal, because metal conducts heat well, so the heat passes quickly to the food. The handle is often plastic or wood, because those do not conduct heat well, so it stays cool enough to hold. If the whole pan were metal, the handle would burn your hand; if the whole pan were plastic, it would melt on the hob. Each part is chosen for its properties and the job it must do. Reading an everyday object this way is the heart of materials science.

Spot the correct science

Tap the TWO statements that are correct science.

• In a solid the particles are packed closely and only vibrate
• A compound has different properties from the elements in it
• An element can be broken down into simpler substances
• In a gas the particles are packed tightly together

Work out the density

A block of material has a mass of 60 grams and a volume of 20 cubic centimetres. Density is mass divided by volume. What is its density, in grams per cubic centimetre?

Pick the right material

For each job, choose the material with the right properties.

• You need the base of a saucepan to pass heat quickly to the food. What property matters most?
• You need a light, waterproof raincoat. What suits it best?
• You are asked whether a piece of pure copper is an element or a compound. What is it?

Build a matter point

Choose the word for each gap to complete one correct science point.

Explain matter and materials

A friend thinks all substances are basically the same stuff. Explain how matter is built from particles, the difference between elements, compounds and mixtures, and how materials are chosen for a job.

• Explain the particle model for solids, liquids and gases
• Explain the difference between an element and a compound
• Explain what a mixture is
• Explain how density is found
• Explain how a material is chosen for its properties