LO 1, 2 Chemical World strand LO 3 Nature of Science strand
18.1 What is matter? . . . . . . . 198 18.2 The atomic nature of matter . . 201 18.3 States of matter . . . . . . . 201 18.4 Changes of state . . . . . . . 203 18.5 Conservation of mass . . . . . 204
Why it matters
The physical world consists of matter and energy. Understanding how they interact is essential to understanding how the physical world operates. Every object in the world around us is composed of matter. Understanding the properties of matter and how they may be changed allows us to discover new uses for existing materials and to create new types of materials.
18.1 What is matter?
Matter Anything that occupies space and has mass.
Mass The amount of matter in an object.
Volume The amount of space an object takes up.
Scientists define matter as anything that takes up space and has mass. Almost everything in the world around us is made of matter. The air, the sea and the mountains are all made of matter. All physical objects, including all living things, are made of matter. We know that these things are made of matter because they occupy space and they have mass. The amount of matter in an object is called its mass. Objects with a large amount of
matter have a large mass and objects with a small amount of matter have a small mass. Scientists can measure the mass of objects. They can also measure the amount of space they take up. This is called the volume. Not everything is composed of matter. Time, gravity and heat are just three things that scientists can measure that are not made of matter.
Activity Make a list of five things that are composed of matter and five things that are not composed of matter.
