chemical change

Question 1

Physical change

Answer 1

properties that you can either observe using your five senses — seeing, hearing, touching, smelling and tasting — or measure directly

Question 2

Chemical Change

Answer 2

properties that describe how a substance combines with other substances to form new chemicals or how a substance breaks up into two or more different substances

Question 3

flammability

Answer 3

an indicator of how easily a substance catches fire

Question 4

reactivity

Answer 4

a measure of how likely a particular metal is to take part in a displacement reaction

Question 5

toxicity

Answer 5

the danger to your health caused when poisonous substances combine with chemicals in your body to produce new substances and damaging effects

Question 6

Melting

Answer 6

Is when a solid is turning into a liquid from a high temperature causing it to melt

Question 7

evaporation

Answer 7

is when liquid is turned into a gas

Question 8

freezing

Answer 8

is when a liquid is to low of a temperature and is frozen into a solid

Question 9

solidification

Answer 9

is when a liquid of high temperature freezes at a high level.

Question 10

condensation

Answer 10

is gas turning into a liquid

Question 11

gas

Answer 11

an air like fluid substance which expands freely to fill any space available, irrespective of its quantity.

Question 12

liquid

Answer 12

a substance that flows freely but is of constant volume, having a consistency like that of water or oil.

Question 13

solid

Answer 13

firm and stable in shape; not liquid or fluid

Question 14

sublimation

Answer 14

is when a solid is turning into a gas

Question 15

deposition

Answer 15

is when a gas is turning into a solid

Question 16

desublimation

Answer 16

is when a gas is turning into a solid

Question 17

chemical reaction

Answer 17

a chemical change in which one or more new chemical substances are produced

Question 18

reactants

Answer 18

chemical substance used up in a chemical reaction. Some chemical bonds in a reactant are broken during the reaction.

Question 19

products

Answer 19

new chemical substance that results from a chemical reaction

Question 20

precipitate

Answer 20

solid product of a chemical reaction that does not dissolve in water

Question 21

rusting

Answer 21

the corrosion of iron

Question 22

corrosion

Answer 22

a chemical reaction that wears away a metal. Air, water or chemicals in air and water, as well as many household substances, can be corrosive. Many acids and other corrosive substances are dangerous.

Question 23

rust

Answer 23

a brown substance formed when iron reacts with oxygen and water

Question 24

surface protection

Answer 24

coating over a metal surface to prevent corrosion

Question 25

galvanising

Answer 25

protecting a metal by covering it with a more reactive metal that will corrode first

Question 26

burning

Answer 26

combining a substance with oxygen in a flame

Question 27

oxidation

Answer 27

chemical reaction involving the loss of electrons by a substance

Question 28

fossil fuel

Answer 28

substance, such as coal, oil and natural gas, that has formed from the remains of ancient organisms. Coal, oil and natural gas are often used as fuels; that is, they are burnt in order to produce heat.

Question 29

combustion

Answer 29

the process of combining with oxygen, most commonly burning with a flame