Chemistry

Question 1

Matter

Answer 1

Anything that occupies space or matter

Question 2

Properties of liquids

Answer 2

Liquids have no defiant shape
Liquids have a definite volume
Liquids cannot be compressed
Liquids can flow

Question 3

Mass

Answer 3

Mass is the amount matter in an object

Question 4

Gases

Answer 4

Gases have no defiant shape
Gases have a definite volume
Gases can be compressed
Gases can flow

Question 5

Properties of solids

Answer 5

Solids have a definite shape, they have a definite volume, they cannot be compressed and cannot flow.

Question 6

Energy

Answer 6

In order for a substance to change state (from a solid to a liquid, or liquid to a gas) it needs heat energy
• As a substance changes state, it uses latent heat. There is no change to temperature, but the state of the material changes.

Answer 7

The melting boint is when both the solid and liquid state existtogether (changing from a solid to a liquid)
The boiling point of a liquid is when evaporation begins to happen throughout the liquid (changing from a liquid to a gas).
• Condensation is the changing of a gas to a liquid.

Answer 8

The meltins o
Msorhen both the solid and
liquid state exist together (changing from a solid to a liquid).
The boilin poirt of a liquid is when evaporation begins to happen throughout the liquid (changing from a liquid to a gas).
Condensation is the changing of a gas to a liquid.
Sublimation: some substances do not change from a solid to a liquid when they melt, they change straight from a solid toa gas.
Eg solid carbon dioxide is known as dry ice, and turns into a gas when heated

Answer 9

Diffusion is the movement of particles from n area of high condentration to an area of low concentration e.g. spray perfume in one corner of the room, and it spreads to the rest of the
room
Solid
Liquid
Gas

Question 10

Physical change

Answer 10

Physical change: no change in particles, just the particle arrangement and energy, easy to reverse e.g. mixing water and salt.

Question 11

Chemical change

Answer 11

Chemical change: A chemical reaction takes place and a new substance is formed, very difficult to reverse e.g. burning a match.

Question 12

During a chemical reaction

Answer 12

During a chemical reaction the atoms rearrange to form a new substance, Might be seen by colour change, temperature change, light being emitted or bubbles.

Question 13

Law of conservation of mass

Answer 13

Malter can be changed from one form to another. During physical and chemical changes, there is no overall change in mass.

Question 14

Filtration

Answer 14

Used to separate small insoluble
solids (do not dissolve in a liquid)
from a liquid by using filter paper
and a funnel to trap the solids. E.g.
sand and water.

Question 15

Evaporation

Answer 15

Used to separate soluble solids
(dissolve in liquids) from a
solution by evaporating off the
liquid to leave the solids. E.g. salt
water.

Question 16

Distillation

Answer 16

Used to separate two liquids with different boiling points such as alcohol (boils at 78o) and water
(boils at 100 o). Also used to separate a soluble solid from a

Question 17

Chromatography

Answer 17

 Used to separate a mixture of
dissolved substances in a
solution. E.g. the different
colours in a black marker.

Answer 18

• Insoluble– does not dissolve in a
  liquid.
• Soluble– dissolves in a liquid.

Answer 19

Residue- the soil left in the filter paper after
filtration

Filtrate- the clean water that comes after
filtration
Evaporation- used to separate a soluble solid
from a liquid e.g. salt and water

Solvent- the liquid that a solid is dissolved
into.

Solute- the solid that is left behind after
evaporation