revision 2

Question 1

latent heat

Answer 1

energy needed for a substance to change

Question 2

enthalpy of heat

Answer 2

energy needed to convert one mole of sold to liquid at melting point

Question 3

enthalpy of vaporisation

Answer 3

energy needed for one mole of liquid to gas at boiling point

Question 4

colbalt chloride

Answer 4

blue when dry, pink with h2o

Question 5

copper sulphate

Answer 5

white when dry, blue with water

Question 6

reactivity series

Answer 6

K
Na
Ca
Mg
Al
C
Zn
Fe
Sn
Pb
H
Cu
Ag
Au
Pt

Question 6

anyhydrous salts

Answer 6

tell you when water is present

Question 7

average atomic mass for isotopes

Answer 7

atomic mass x % + how many there are/ 100

Question 8

positively charged ions

Answer 8

cations

Question 9

negative charged ion

Answer 9

anions

Question 10

mole formula

Answer 10

mass= mr x moles

Question 11

calculating energy change (entalphy diagrams)

Answer 11

broken bonds- bonds made
(negative shows a endothermic)

Question 12

electrolysis

Answer 12

using electricity to split water to h and o

Question 13

rate of reaction formula

Answer 13

products formed (g/cm^3)/time taken (s)

Question 14

oxidation

Answer 14

loss of electrons, becomes positive, charge decreases

Question 15

reduction

Answer 15

gains electrons, charge increases

Question 17

ions- 5

Answer 17

OH, SO4^-2, NH4+, CO3^-2, NO3-

Question 18

HADIES test (group 7)

Answer 18

add dilute nitric acid to remove carbonate ions, add silver nitrate

Question 19

hadies test results
cl, br, i

Answer 19

cl- white
br- cream
i- yellow

Question 20

blue cobalt chloride paper turns…. with water

Answer 20

pink

Question 21

oxidies which can react with acids and bases are

Answer 21

amphoteric

Question 22

metal oxides are basic and ionic the react with acids and form

Answer 22

salts and water

Question 23

2 examples of emphoteric (can react as acid or base)

Answer 23

zinc oxide
aluminium oxide

Question 24

group 8

Answer 24

nobel gases
dont react
low density

Question 25

group 1 `

Answer 25

alkali metals
soft
shiny but tarnish
melting point decreases
density increases
all react with water, stored in oil

Question 26

group 7- (8 things)

Answer 26

halogens
produce salts when react with metals (ionic) to form halide salts
As elements, they exist as diatomic molecules (contain 2 atoms shared covalently)
Increasing darkness, density and melting point,
reactivity decreases
can displace each other

Question 27

transition metals

Answer 27

act as a catalyst
high densities
melting points range (mercury liquid at room temp)
elements can form ions by losing diffrent number of e (variable oxidation numbers)

Question 28

npk fertiliser

Answer 28

nitrogen, phosphorus, potassium, replace what plant takes

Question 29

air has

Answer 29

78% nitrogen, 21% oxygen, 1% others. nitrogen is stable but o2 keeps getting added and removed

Question 30

photosynthesis word equation

Answer 30

co2+ ater= c6h12o6+ o2

Question 31

particulates

Answer 31

small enough to circle in air, cause breathing issues

Question 32

homologous series

Answer 32

same functional group
same chemical properties
diffrent physical properties
similar method of preparation