Matter

Question 1

Define matter

Answer 1

Matter is anything that has mass and occupies space

Question 2

What is matter composed of?

Answer 2

Discrete, tiny, fundamental particles called atoms

Question 3

How is matter classified?

Answer 3

According to its physical state and composition

Question 4

Classify matter according to its physical state.

3

Answer 4

Gas
Liquid
Solid

Question 5

Classify matter according to its composition

3

Answer 5

Element
Compound
Mixture

Question 6

Write a note on the physical state of solids

5

Answer 6

Definite shape
Definite volume
Essentially incompressible
Particles are tightly packed together
Particles are held together by very strong forces of attraction

Question 7

Describe the physical state of the particles in solids.

Answer 7

The particles are tightly packed together

The particles are held together by very strong forces of attraction

Question 8

Write a note on the physical state of liquids.

5

Answer 8

Indefinite shape
Definite volume
Only slightly compressible
Particles are mobile, able to move around each other
Particles are held together by strong forces of attraction

Question 9

Describe the physical state of the particles in liquids

Answer 9

Particles are mobile, able to move around each other

Particles are held together by strong forces of attraction

Question 10

Write a note on the physical state of gases

5

Answer 10

Indefinite shape
Indefinite volume
Compressible
Particles are far apart and are small compared to the volume they occupy
The attractive forces are so weak that the particles are independent of each other

Question 11

Describe the physical state of the particles of a gas.

Answer 11

Particles are far apart and are small compared to the volume they occupy
The attractive forces are so weak that the particles are independent of each other

Question 12

Describe the movement of molecules in a solid.

Answer 12

Molecules vibrate about a fixed average position

Question 13

Describe the movement of molecules in a liquid

Answer 13

Molecules can move past each other, but there are many collisions

Question 14

Describe the movement of molecules in a gas

Answer 14

Molecules move rapidly in random directions

Question 15

In what two ways can matter exist?

Answer 15

As a pure substance or as a mixture

Question 16

Define a pure substance.

2

Answer 16

Uniform and fixed composition

Elements and compounds exist as pure substances if only one kind of matter is present

Question 17

When can elements and compounds exist as pure substances?

Answer 17

If only one kind of matter is present

Question 18

Define an element in terms of matter

Answer 18

A pure substance composed of only one type of atom e.g. Cu (copper)

Question 19

Define a compound in terms of matter

Answer 19

A pure substance composed of more than one element

Question 20

Give the definition of an element.

Answer 20

An element is a substance that cannot be separated into simpler substances by chemical means

Question 21

How many elements have been discovered?

Answer 21

118 elements

Question 22

How many elements occur naturally on Earth?

Answer 22

94

Question 23

What four elements make up 96% of living matter?

Answer 23

Oxygen O
Carbon C
Hydrogen H
Nitrogen N

Question 24

What is the definition of a compound?

Answer 24

A chemical compound is a pure chemical substance of two or more different chemical elements that can be separated into simpler substances by chemical reactions

Question 25

Classify pure substances.

Answer 25

Elemental substance Compound

Question 26

Classify mixtures

Answer 26

Homogeneous mixture Heterogeneous mixture

Question 27

What is a homogeneous mixture also known as?

Answer 27

A solution

Question 28

Describe the composition of a homogeneous mixture.

Answer 28

Uniform throughout

Question 29

Describe the composition of a heterogeneous mixture.

Answer 29

Not uniform throughout

Question 30

Define a mixture. | 2

Answer 30

A combination of two or more substances that are not chemically united and do not exist in fixed proportions to each other Can be physically separated into pure compounds or elements

Question 31

Define a solution

Answer 31

A mixture of two or more substances in a single phase At least two substances must be mixed to have a solution

Question 32

Describe homogeneous matter.

Answer 32

Homogeneous matter is uniform in appearance and has the same properties throughout

Question 33

Give an example of a homogeneous mixture

Answer 33

Sugar and water

Question 34

Describe heterogeneous matter

Answer 34

Heterogeneous matter consists of two or more physically distinct phases

Question 35

Define a phase

Answer 35

A phase is a homogeneous part of a system separated from other parts by physical boundaries

Question 36

Give an example of a pure substance heterogeneous mixture

Answer 36

Liquid and gaseous bromine

Question 37

Give an example of a mixture of heterogeneous matter.

Answer 37

Iced tea

Question 38

What is a physical change?

Answer 38

A change that does not result in a change of composition

Question 39

What is a chemical change

Answer 39

When a substance changes its composition

Question 40

Under what condition can mixtures be separated?

Answer 40

Mixtures can be separated if their physical properties are different

Question 41

What is the name of the method used to separate solids from liquids?

Answer 41

Filtration

Question 42

Describe the process of filtration.

Answer 42

The solid is collected in filter paper while the solution (filtrate) passes through the filter paper and is collected in a flask

Question 43

How can homogeneous liquids be separated?

Answer 43

They can be separated by distillation

Question 44

What is required for distillation to work?

Answer 44

The different liquids must have different boiling points

Question 45

What methods are used to isolate pure substances from each other?

Answer 45

Chromatography Filtration Distillation etc