EXAM

Question 1

electrons

Answer 1

negative

Question 2

neutrons

Answer 2

neutral (no charge)

Question 3

how do you calculate the number of neutrons

Answer 3

atomic mass (rounded) - atomic number

Question 4

what is the central area of an atom called

Answer 4

the nucleus

Question 5

what is the law on conservation of matter

Answer 5

matter can never be destroyed or created but it can be changed

Question 6

physical change definition

Answer 6

a chnage where the matter looks different but is still made of the same substance or chemical

Question 7

chemical change definition

Answer 7

a chnage where a new substance is formed

Question 8

how can you know it’s a chemical chnage

Answer 8

• a new solid has formed
• a new gas has formed
• a new colour is visible that doesn’t go away
• a change im temperature
• a pH change

Question 9

what is a chemical reaction

Answer 9

when you mix two or more chemicals and get new chemicals

Question 10

what are the chemicals you mix called

Answer 10

reactants

Question 11

what are the new chemicals you make called

Answer 11

products

Question 12

solid to liquid

Answer 12

melting

Question 13

gas to liquid

Answer 13

condensation

Question 14

solid to gas

Answer 14

sublimation

Question 15

liquid to solid

Answer 15

solidification

Question 16

gas to solid

Answer 16

deposition

Question 17

liquid to gas

Answer 17

boiling of evaporation

Question 18

another term for solidification

Answer 18

freezing

Question 19

another term for liquefaction

Answer 19

melting

Question 20

another term for boiling

Answer 20

evaporation

Question 21

another term for vaporization

Answer 21

evaporation or boiling

Question 22

molecules (solid is being heated)

Answer 22

• particles are very close

* barely moving

Question 23

molecules (melting)

Answer 23

• some particles are close some are moving apart

* moving slowly

Question 24

molecules (heating liquid)

Answer 24

• particles are all separated

* moving at medium speed

Question 25

molecules (boiling evaporation)

Answer 25

* particles widely separated | * moving quickly

Question 26

what phase chnage occurs when wet clothes dry outside

Answer 26

evaporation

Question 27

what is an example of sublimation

Answer 27

the solid stick deodorant in the bathroom giving off its odour

Question 28

what is characteristics

Answer 28

things that we can use to describe something

Question 29

characteristic properties

Answer 29

things that can be used to identify sonethig

Question 30

non characteristic properties

Answer 30

things that can be described something but not identify what is it