Classification Of Matter

Question 1

The Particle Theory

Answer 1

All matter is made up of tiny particles.
All particles of one substance are the same. Different substances are made of different particles.
The particles are always moving. The more energy the particles have, the faster they move.
There are attractive forces between the particles. These forces are stronger when the particles are closer together.

Question 2

Pure Substances

Answer 2

A pure substance is made up of only one kind of matter
Has a unique set of properties
colour, hardness, boiling point, and melting point.
A pure substance is either an element or a compound

Question 3

Element

Answer 3

A pure substance that cannot be broken down into any simpler substance by chemical means.
Each element has its own name and symbol. Example: Gold (Au)

Question 4

Compound

Answer 4

A pure substance that is made from two or more elements that are combined together chemically.
Example, water (H2O) is a compound containing the elements hydrogen and oxygen.

Question 5

Mixture

Answer 5

A mixture is a combination of pure substances.
Each substance remains in its original, pure form, although each is not always easy to see distinctly once the mixture is made.
A mixture is either a mechanical mixture, a suspension/colloid, or a solution

Question 6

Mechanical Mixture (heterogeneous mixture)

Answer 6

Different substances that make up the mixture are visible

Hetero = different

Question 7

Suspension

Answer 7

A heterogeneous mixture, in which the particles settle slowly after mixing, is called a suspension (eg. orange juice)
Can be separated by filtration
Particles are larger than in a colloid

Question 8

Colloid

Answer 8

a heterogeneous mixture, in which particles do not settle at all, is called a colloid (eg. fog)
The dispersed particles of a colloid cannot be separated by filtration, but they scatter light (called Tyndall effect)
Particles are smaller than in a suspension but larger than in a solution

Question 9

Solution (homogeneous mixture)

Answer 9

Different substances that make it up are not individually visible
One substance is dissolved in another
The prefix “homo-” means same, and all parts of a homogeneous mixture look the same.