chemistry

12 the diagram shows the apparatus used to measure the rate of a chemical reaction.
‘— reactants
—_— i
li
balance se +739

for which reaction can the rate be measured using this apparatus?

a 2na + clz > 2nacl

b naoh + hcl + nacl + h,0

c na,o + 2hcl > 2nacl + ho

d nasco3; + 2hci > 2nacl + h,0 + co,

13 copper(ii) carbonate reacts with dilute sulfuric acid.
cuco;(s) + h2so,(aq) > cuso,(aq) + co2(g) + h20(i)
the rate of the reaction can be changed by varying the conditions.
which changes always increase the rate of this chemical reaction?
1 increasing the concentration of sulfuric acid
2 increasing the size of the pieces of copper(ii) carbonate
3. increasing the temperature
4 increasing the volume of sulfuric acid
a 1,3and4 b iand3only c 2and3 d 3and4 only

15 the equation for the effect of heat on hydrated sodium carbonate is as shown.
nazco3.10h20(s) = na,co,(s) + 10h,o(g)
statements made by four students about the reaction are given.
p_ anhydrous sodium carbonate is formed.
q_ steam is formed.
r_ there is a colour change from blue to white.
s_ the reaction is reversible.
which students’ statements are correct?
a p, qand r only
bp, qand s only
c q,rand s only
d p,q,rands

25 two experiments are carried out.
in experiment 1, copper is heated with steam.
in experiment 2, copper(ii) oxide is heated with carbon.
copper(ii) oxide
and carbon
steam _ a1 ————_ ra _
—
copper t
heat
experiment 1 experiment 2
which row describes what happens in experiments 1 and 2?
[| experiment | experimen 2 |
a no reaction no reaction
b no reaction reaction
cc reaction no reaction
d reaction reaction

28 vvater is added to hydrated copper(11) sulfate.
0
nem hydrated
copper(ii) sulfate
which colour change takes place?
a blue to pink
b _ blue to white
c nochange
d_ white to blue

12 magnesium carbonate was reacted with dilute hydrochloric acid in a conical flask.
the conical flask was placed on a balance and the mass of the conical flask and contents was
recorded as the reaction proceeded.

during the reaction, carbon dioxide gas was produced.
the reaction was done at two different temperatures.
which row is correct?
[aera sr,
mass changed more quickly
a decrease higher temperature
b decrease lower temperature
c increase higher temperature
d increase lower temperature

13 separate samples of anhydrous copper(ii) sulfate and hydrated copper(ii) sulfate are heated.
/ anhydrous | hydrated
copper(ii) sulfate copper(ii) sulfate
heat heat
which row shows the correct colour changes?
| | anhydrous copper(ii) sulfate hydrated copper(ii) sulfate
a blue to white white to blue
b no change blue to white
cc white to blue blue to white
d white to blue no change

1 four processes are listed.
1 brownian motion
2 condensation
3 diffusion
4 evaporation
which processes involve a change of state?
a i1and2 b 1and3 c 2and4 d 3and4

12 which process involves a chemical change?
a_ dissolving copper(ii) sulfate
b distilling ethanol
c_ freezing water
d neutralising copper(ii) oxide

13 lumps of limestone react with dilute hydrochloric acid according to the equation shown.
caco3 + 2hcl + cacl, + h,0 + coz
which change in conditions decreases the rate of the reaction?
a increase the concentration of the acid
b_ increase the volume of the acid
c increase the size of the lumps of limestone
d_ increase the temperature

14 which reaction is reversible?
a cu + znso, — cuso, + zn
b cuo + h,so,4 > cuso, + h20
c cuo + hz > cu + h,0
d cuso,*5h20 -— cuso, + 5h20

33 which element has an oxide that is used as a food preservative?
a helium
b_ hydrogen
c_ iron
d © sulfur

13 the diagram shows the change from an anhydrous salt to its hydrated form.
forward
=

reverse

which statement is correct?

a_ the forward reaction requires heat and water.

b_ the forward reaction requires water only.

c_ the reverse reaction requires heat and water.

d_ the reverse reaction requires water only.

15 when zinc carbonate is mixed with dilute hydrochloric acid a change, m, takes place.
when carbon is heated with copper(ii) oxide a change, n, takes place.
which row describes changes m and n?
ee ee
a chemical chemical
b chemical physical
cc physical chemical
d physical physical

16 the apparatus shown is used to measure the rate of a reaction.
gas syringe
reactants
which equation represents a reaction where the rate can be measured using this apparatus?
a mg(s) + 2hcl(aq) > mgci2(aq) + h2(9)
b  hcl(aq) + naoh(aq) > nacl(aq) + h20(i)
c fe(s) + cuso,(aq) > cu(s) + fesox(aq)
d 2na(s) + br2(l) > 2nabr(s)

17 asequence of changes involving sulfur is shown.
change 1 change 2
s —— s$ —— 50,
solid liquid gas
which row describes the changes?
[ [tango | ehansea |
a chemical chemical
b chemical physical
cc physical chemical
d physical physical

18 magnesium is added to dilute hydrochloric acid.
25 cm? of gas is given off in the first 30 s of the reaction.
the experiment is repeated at a lower temperature. all other reaction conditions are the same.
which volume of gas is produced in the first 30s of this reaction?
a 15cm? b 25cm? c 30cm° d 50cm°

19 the equation for the reaction between magnesium and copper(ii) oxide is shown.
mg + cuo + mgo + cu
which substance is oxidised?
a cu b cuo c mg d mgo

13 which row describes a chemical change?
[| oa
are made change of state

a always always

b always sometimes

cc never always

d never sometimes

a

15 which statement about hydrated cobalt(ii) chloride is correct?
a it turns blue when it is heated.
b it turns blue when water is added to it.
c it turns pink when water is added to it.
d it turns white when it is heated.

12 which row describes the changes that occur when metals burn in oxygen?
[| eerie [etal
a decreases oxidised
b decreases reduced
cc increases oxidised
d increases reduced

17 anexperiment is set up as shown.
the mass of the conical flask and its contents is measured at 30-second intervals.
50 cm* dilute hydrochloric acid
(nl 1g calcium carbonate
m 0 ss
which statement about the reaction and changes to the reaction conditions is correct?
a adding 10cm’ of water to the 50cm’ of acid increases the rate of the reaction.
b increasing the size of the pieces of calcium carbonate increases the rate of the reaction.
c_ increasing the temperature increases the rate of the reaction.
d_ the mass of the conical flask and its contents increases as carbon dioxide is formed.

6
15 a student was investigating the reaction between marble chips and di
gas syri
bung
marble
chips 25cm of dilute
bem ead hydrochloric acid
which changes slow down the rate of reaction?
temperature concentration surface area
of acid of acid of marble chips
a decrease decrease decrease
b decrease decrease increase
cc increase decrease decrease
d increase increase increase
16 the reactions shown may occur in the air during a thunder-storm.
no + o2 — 2no
2no + oo > 2no>2
no + o3 — no» + oo
which row shows what happens to the reactant molecules in each of

15 astudent was investigating the reaction between marble chips and dilute hydrochloric acid.
gas syringe
— pf
marble
chips 25cm of dilute
bemea j hydrochloric acid
which changes slow down the rate of reaction?
temperature concentration surface area
of acid of acid of marble chips
a decrease decrease decrease
b decrease decrease increase
cc increase decrease decrease
d increase increase increase

16 the reactions shown may occur in the air during a thunder-storm.
n2 + o2 + 2no
2no + o2 > 2no,
no + o3 — noz + o2
which row shows what happens to the reactant molecules in each of these reactions?
[to [fo |
a oxidised oxidised oxidised
b oxidised oxidised reduced
cc reduced reduced oxidised
d reduced reduced reduced

14 which colour change is seen when hydrated cobalt(ii) chloride is heated so that it becomes
anhydrous cobalt(ii) chloride?
a blue to pink
b _ blue to white
c pink to blue
d_ white to blue

15 a student was investigating the reaction between marble chips and dilute hydrochloric acid.
gas syringe
— |
marble
chips 25cmé* of dilute
bem ea) hydrochloric acid
which changes slow down the rate of reaction?
temperature concentration surface area
of acid of acid of marble chips
a decrease decrease decrease
b decrease decrease increase
cc increase decrease decrease
d increase increase increase

16 the reactions shown may occur in the air during a thunder-storm.
n2 + o2 + 2no
2no + o2 > 2no2
no + o3 — no, + o2
which row shows what happens to the reactant molecules in each of these reactions?
fos [we te
a oxidised oxidised oxidised
b oxidised oxidised reduced
cc reduced reduced oxidised
d reduced reduced reduced

12 the diagram shows a rate of reaction experiment.
hydrogen
. oa excess dilute
magnesium 5 cccartt 5
ig (28.95 hydrochloric acid at 25°c
increasing the concentration of the acid and increasing the temperature both affect the rate of
reaction.
which row is correct?
increase the concentration ‘
4 increase the temperature
of acid
a decrease rate of reaction decrease rate of reaction
b decrease rate of reaction increase rate of reaction
cc increase rate of reaction decrease rate of reaction
d increase rate of reaction increase rate of reaction
a

32 which statement about sulfur and its compounds is not correct?
a sulfur dioxide is used as a food preservative.
b_ sulfur dioxide turns acidified aqueous potassium manganate(vii) from purple to colourless.
c_ sulfur forms a basic oxide.
d_ sulfur is used in the manufacture of sulfuric acid.

12 the diagram shows a rate of reaction experiment.
he
hydrogen
: os excess dilute
magnesium a .
i) (8c. hydrochloric acid at 25°c
increasing the concentration of the acid and increasing the temperature both affect the rate of
reaction.
which row is correct?
increase the concentration ‘
: increase the temperature
of acid
a decrease rate of reaction decrease rate of reaction
b decrease rate of reaction increase rate of reaction
cc increase rate of reaction decrease rate of reaction
d increase rate of reaction increase rate of reaction

13 reaction x shows a test for water. reaction y occurs in the blast furnace for extracting iron.
reaction x coclz + 6h20 = cocl2.6h20
reaction y c + cq, ~ 2co
reaction x is ......1...... . in reaction y, the oxide cosz is ......2.......
which words correctly complete gaps 1 and 2?
pop te
a irreversible oxidised
b irreversible reduced
cc reversible oxidised
d reversible reduced

39 the equations for two important processes used to manufacture ethanol are shown.

process 1 cghi20g — 2c2h50h + 2co2
process 2. csh, + hxo > czhsoh

which statement is not correct?

a_ both processes require a catalyst.

b_ both processes use a starting material obtained from petroleum.

c_ process 1 shows the production of a renewable fuel.

d_ process 2 is an addition reaction.

13 in achemical reaction, blue compound x changed into white compound y.
xx > y
blue white
which statement describes this reaction?
a hydrated cobalt(ii) chloride is heated.
b_ hydrated copper(ii) sulfate is heated.
c_ water is added to anhydrous cobalt(ii) chloride.
d_ water is added to anhydrous copper(ii) sulfate.

12 which process is a physical change?
a burning wood
b_ cooking an egg
c_ melting an ice cube
d__rusting iron

13 hydrogen peroxide solution decomposes very slowly at room temperature to produce oxygen
gas. this gas forms a rising foam when liquid detergent is added.
five test-tubes are half filled with hydrogen peroxide solution. a drop of liquid detergent is added
to each one.
different metal oxides are added to four of the test-tubes and the height of the foam formed after
1 minute is measured. the results are shown.
no metal oxide added 0.1
aluminium oxide 0.1
calcium oxide 0.2
copper(ii) oxide 23
manganese(iv) oxide 5.4
which conclusion can be drawn from these results?
a_ metal oxides do not affect the rate of this reaction.
b_ all metal oxides increase the rate of this reaction and act as catalysts.
c manganese(iv) oxide is the best catalyst of the four metal oxides tested.
d_ only transition element oxides increase the rate of this reaction.

14 when blue-green crystals of nickel(ii) sulfate are heated, water is produced and a yellow solid
remains. when water is added to the yellow solid, the blue-green colour returns.
which process describes these changes?
a combustion
b_ corrosion
c neutralisation
d_ reversible reaction

30 the diagram shows an experiment to investigate how paint affects the rusting of iron.
p q
iron painted iron
air
water

what happens to the water level in tubes p and q?
[ter [ue |

a falls rises

b no change rises

cc rises falls

d rises no change

12 which process is a physical change?
a a firework exploding
b burning wood
c_ chocolate melting
d iron rusting

13 an experiment is set up as shown.
the mass of the conical flask and its contents is measured at 30 second intervals.
50cm dilute hydrochloric acid
nl 1g calcium carbonate
li
which statement about the reaction and about changes to the reaction conditions is correct?
a adding 10cm* of water to the 50cm* of acid increases the rate of the reaction.
b_ increasing the size of the pieces of calcium carbonate increases the rate of the reaction.
c_ increasing the temperature increases the rate of the reaction.
d_ the mass of the conical flask increases as carbon dioxide is formed.

15 different types of reaction are listed.
1 oxidation
2 decomposition
3 combustion
4 reduction
the equation shows the reaction of magnesium with oxygen.
2mg + o2 > 2mgo
which types of reaction does magnesium undergo in this reaction?
a 1tand3 b_ 1only c 2and4 d 4only

30 the diagram shows an experiment to investigate how paint affects the rusting of iron.
le q
iron painted iron
air
water

what happens to the water level in tubes p and q?
[weer ae

a falls rises

b no change rises

cc rises falls

d rises no change

11. which row describes the changes that occur when metals burn in oxygen?
[| temperature [mets
a decreases oxidised
b decreases reduced
cc increases oxidised
d increases reduced

30 the diagram shows an experiment to investigate how paint affects the rusting of iron.
p q
iron painted iron
air
water

what happens to the water level in tubes p and q?
[uber abe

a falls rises

b no change rises

cc rises falls

d rises no change

17 phosphorus is an element in group v of the periodic table.
it burns in air to form an oxide, which dissolves in water to form a solution with a ph of 1.
which row describes this oxide of phosphorus?
[as po os
oxide oxide oxide oxide
a v x v x
b v x x v
cc x v v x
d x v x v

13 which row shows the changes that all increase the rate of a chemical reaction?
concentration ’ :
temperature particle size
of reactants
a decrease decrease decrease
b decrease increase increase
cc increase decrease increase
d increase increase decrease

14 when sulfur is heated it undergoes a ......1...... change as it melts.
further heating causes the sulfur to undergo a ......2...... change and form sulfur dioxide.
which words complete gaps 1 and 2?
1 2
a chemical chemical
b chemical physical
cc physical chemical
d physical physical

16 which statement is correct?
a when anhydrous copper(ii) sulfate is heated its colour changes to a deeper blue.
b when hydrated copper(ii) sulfate is heated its colour changes to a deeper blue.
c when water is added to blue cobalt(ii) chloride paper it turns pink.
d when water is added to pink cobalt(ii) chloride paper it turns blue.

20 some reactions of element m are shown.
burn . add water .
element m | ————©- | oxide of m| ——————- | solution
add to purple acidified add blue lias
potassium manganate(vii)
what is element m?
a carbon
biron
c magnesium
d © sulfur

2 solid carbon dioxide changes directly into a gas under suitable conditions of temperature and
pressure.
carbon dioxide gas moves from a high concentration to a low concentration.
which row names these two processes?
changing from mowing tot a
‘ging high concentration to
solid to gas ;
a low concentration
a evaporation brownian motion
b evaporation diffusion
cc sublimation brownian motion
d sublimation diffusion

14 when sultur is neated it undergoes a......1...... change as it meits.
further heating causes the sulfur to undergo a.......2...... change and form sulfur dioxide.
which words complete gaps 1 and 2?
ee
a chemical chemical
b chemical physical
cc physical chemical
d physical physical

17 copper(ii) oxide reacts with iron. the equation for the reaction is shown.
3cuo + 2fe + 3cu + fe203
why can this reaction be described as the reduction of copper(ii) oxide?
a iron gains oxygen.
b_ the copper(ii) oxide loses oxygen.
c_ the copper(ii) oxide weighs less after the reaction than before.
d_ there are fewer substances on the right of the equation.

16 excess magnesium ribbon is reacted with a fixed volume of hydrochloric acid and the volume of
gas given off over time is measured.
the results of two different experiments are shown.
reaction 1
volume of gas
givers ot reaction 2
0
0 time
which statement explains the differences between the results of the two experiments?
a reaction 1 uses a catalyst.
b_ the acid used is twice as concentrated in reaction 1.
c the magnesium ribbon is in smaller pieces in reaction 2.
d_ the temperature is higher in reaction 2.

39 the equation representing the reaction of a hydrocarbon with water is shown.
catalyst
c,h, + hq ——————-» c,h;0h
what are the values of x and y?
pf «x [yy |
a 1 4
b 1 6
cc 2 4
d 2 6

1 substances change state when their temperature is changed.
which changes of state take place when the temperature of a substance is lowered?
1 boiling
2 condensation
3. freezing
4 melting
a 1and4 b 2,3 and4 c 2and3only d = 3only

13 which statement about rate of reaction is correct?
a catalysts increase the time for the reaction to be completed.
b_ decreasing particle size increases the rate of reaction.
c_ decreasing temperature increases the rate of reaction.
d_ rate of reaction decreases as the concentration increases.

13 metal m reacts with steam and produces gas g.
which row identifies gas g and the type of reaction when metal m reacts with steam?
[ces ¢ | ype treason |
a hydrogen redox
b hydrogen neutralisation
cc oxygen redox
d oxygen neutralisation

14 the rate of the reaction between lumps of zinc and dilute sulfuric acid is determined.
the experiment is repeated four times, making only one change each time.
the changes are listed.
1 the lumps of zinc are replaced with powdered zinc.
2 water is added to the dilute sulfuric acid.
3. the temperature of the dilute sulfuric acid is increased.
4  acatalyst is added to the reaction mixture.
which changes produce an increase in the rate of reaction?
a 1,3 and4 b 1and2 c 2only d 3and 4 only

12 which changes increase the rate of reaction?
1 increasing the concentration of the reactants
2 __ increasing the particle size of a solid reactant
3. increasing the temperature
a 1,2and3 b 1tand2only c 1and3only d 2and3only

27 which compound is formed when iron rusts?
a anhydrous iron(ii) oxide
b anhydrous iron(ii) oxide
c hydrated iron(iii) hydroxide
d hydrated iron(ii) oxide

12 which row shows the changes that all increase the rate of a chemical reaction?
concentration : ‘
temperature particle size
of reactants
a decrease decrease decrease
b decrease increase increase
cc increase decrease increase
d increase increase decrease

13 a student heats hydrated copper(ii) sulfate. the blue crystals change to a white powder.
how can the student reverse this reaction?
a add anhydrous copper(ii) sulfate to the white powder.
b_ add water to the white powder.
c cool the white powder.
d_ reheat the white powder.

14 acidified aqueous potassium manganate( vii) is a purple solution.
what does the (vii) in the name potassium manganate(vii) represent?
a_ the charge on the potassium ion
b_ the charge of the manganate ion
c the number of ions in the compound
d the oxidation number of manganese

35 which process involves combustion?
(some of the reaction products are not shown on the diagram.)
.
a
in water
d
° pewenere)

1. the diagram shows how the arrangement of particles changes when a substance changes state.
eoeeees
which change of state is shown?
a boiling
b_ condensation
c_ evaporation
d sublimation

14 when blue copper(ii) sulfate is heated, a white solid and water are formed.
the white solid turns blue and gives out heat when water is added to it.
which terms describe the blue copper(ii) sulfate and the reactions?

tee reactions
copper(ii) sulfate is
a a mixture can be reversed
b a mixture cannot be reversed
cc hydrated can be reversed
d hydrated cannot be reversed

16 the equations for two reactions p and q are given.
p 2nanqz + o2 > 2nano3
q 2hgo > 2hg + o2
in which of these reactions does oxidation of the underlined substance occur?
a v v
b v x
cc x v
d x x

14 when blue copper(ii) sulfate is heated, a white solid and water are formed.
the white solid turns blue and gives out heat when water is added to it.
which terms describe the blue copper(ii) sulfate and the reactions?

the blue reactions
copper(ii) sulfate is
a a mixture can be reversed
b a mixture cannot be reversed
cc hydrated can be reversed
d hydrated cannot be reversed

15 an experiment was carried out to find the rate of reaction when 1g of solid x reacts with 100 cm*®
of solution y.
ce |
: \
gas syringe
solution y
solid x a
the experiment took place too quickly for measurements to be made.
which change could be made to slow down the reaction?
a add acatalyst
b_ decrease the concentration of solution y
c_ decrease the particle size of solid x
d_ increase the temperature

16 the equations for two reactions p and q are given.
p 2nanqz + o2 > 2nano3
q 2hgo > 2hg + o,
in which of these reactions does oxidation of the underlined substance occur?
a jv v
b v x
cc x v
d x x

15 the equation for the reaction between magnesium and hydrochloric acid is shown.
mg + 2hci + mgcl2 + he
the rate of this reaction is studied using the apparatus shown.
z z gas syringe
hydrochloric acid
magnesium ribbon
which change increases the rate of reaction?
a lowering the temperature of the acid
busing a larger volume of the same hydrochloric acid
c using less concentrated hydrochloric acid
d_ using the same mass of magnesium powder

16 the equations for two reactions p and q are given.
p 2nanoz + o2 > 2nano;
q 2hgo > 2hg + o2
in which of these reactions does oxidation of the underlined substance occur?
a v v
b v x
cc x v
d x x

2 the pressure of a sample of gas is decreased. the temperature is kept constant.
which row describes the effects on the particles?
' collisions between
movement of particles é
particles
a slower occur less often
b slower occur with more force
cc no change in speed occur less often
d no change in speed occur with more force

14 iwo reactions are done.
1 hydrated cobalt(ii) chloride is heated. it changes colour.
2 water is added to the product of reaction 1. it becomes hotter. the original colour is
produced.
which types of reaction have occurred in reactions 1 and 2?
[| endetremic | exotemie | neutaisaton | reversible _|
a v v v v
b v v jv x
cc v v x v
d v x x v

14 a student heats hydrated copper(ii) sulfate. the blue crystals change to a white powder.
how can the student reverse this reaction?
a_ add anhydrous copper(ii) sulfate to the white powder.
b_ add water to the white powder.
c_ cool the white powder.
d_ reheat the white powder.

16 in experiment 1, 1g of calcium carbonate is reacted with an excess of dilute hydrochloric acid.
the volume of gas produced every minute is recorded.
in experiment 2, experiment 1 is repeated using smaller pieces of calcium carbonate. all other
conditions are kept the same.
the results from both experiments are shown.
ners [0 | 60 [120 | 10 | 200 |
volume of gas from 172 212 220
experiment 1/cm
sale te at eats tata 157 | 209 | 220 | 220
experiment 2/cm
which statement about experiment 2 is correct?
a_ the rate of reaction is faster than in experiment 1 and there is the same amount of product.
b_ the rate of reaction is faster than in experiment 1 and there is more product.
c_ the rate of reaction is the same as in experiment 1 and there is the same amount of product.
d_ the rate of reaction is the same as in experiment 1 and there is more product.

14 when solid hydrated cobalt(ii) chloride crystals are heated they turn blue and steam is produced.
adding water to the blue crystals turns them pink.
which type of reaction has occurred?
a neutralisation
b_ oxidation
c_ reduction
d_ reversible

12 tquations for the formation of annydrous cobait(1l) chloride and anhydrous copper(il) sulfate are
shown.
cocl2*6h20 — cocl2z + 6h20
cuso,4*5h20 — cuso, + 5h20
which statement about the reactions is not correct?
a_ both reactions are exothermic.
b_ both reactions are reversible.
c_ hydrated cobalt(ii) chloride changes colour from pink to blue.
d_ hydrated copper(ii) sulfate changes colour from blue to white.

15 mercury(ii) oxide, hgo, decomposes when heated.
the equation is shown.
2hgo — 2hg + oo
why is this a reduction reaction?
a_ the products weigh less than the reactants.
b_ there are fewer reactants than products.
c_ there is a gain of oxygen.
d_ there is a loss of oxygen.

12. which reaction produces a white-coloured substance?
a adding water to anhydrous cobalt(ii) chloride
b_ adding water to anhydrous copper(ii) sulfate
c heating hydrated cobalt(ii) chloride
d heating hydrated copper(ii) sulfate

12 hydrated cobalt(ii) chloride decomposes when heated.
cocl26h20 ———® cocl2 + 6h20
which statements about this reaction are correct?
1 coclz is anhydrous cobalt(ii) chloride.
2 heat is released when water is added to coclo.
3 cocl,*6h,0 is blue.
4 the reaction is not reversible.
a 1and2 b 1and3 c 2and4 d 3and4

14 a sequence of changes involving sulfur is shown.
change 1 change 2
s(s) ————> sil) ————> s0,(g)

which row describes the changes?
[| aneet[ tana?

a chemical chemical

b chemical physical

cc physical chemical

d physical physical

22 which statement does not describe a transition element?
a itis used as a catalyst in industrial reactions.
b_ it has white compounds and gives a yellow flame test.
c_ it produces a black oxide and a blue sulfate.
d_ it forms green, violet and orange compounds.

1 ‘the movement of a substance very slowly from an area of high concentration to an area of low
concentration.’
which process is being described?
a aliquid being frozen
b_ asolid melting
ca substance diffusing through a liquid
d  asubstance diffusing through the air

2 what happens to the average speed of gas particles when pressure and temperature are
increased?
so
a faster faster
b unchanged slower
cc slower faster
d unchanged faster

20 when pink crystals of cobalt(ii) chloride are heated, steam is given off and the colour of the solid
changes to blue.
coclz*6h20 = cocl, + 6h20
what happens when water is added to the blue solid?
[cour [temperate |
a changes to pink decreases
b changes to pink increases
cc remains blue decreases
d remains blue increases

21 in which change is the sulfur, s, in sulfur(i) oxide, s20, reduced?
so,
i
ss a. $,0 es so,
|:
so

17 nitrogen, nz, and hydrogen, h2, can be converted into ammonia, nh3, using a catalyst.
what is the purpose of the catalyst?
a _toincrease the amount of ammonia produced
b to increase the rate of reaction
c_ to reduce the amount of reactants needed
d_ to reduce the rate of reaction

18 a reaction is carried out at four different temperatures.
the time taken for the reaction to complete at each temperature is measured.
the results are shown.
wt _1 [| [| [| [|
60
o__| nh | | |
ot} ia] | ft
times | | |
30
nf} | ko} | |
oo
oe
0 10 20 30 40 50 60
temperature /°c
what is the relationship between temperature and rate of reaction?
a_ the rate decreases as the temperature increases.
b_ the rate increases as the temperature increases.
c_ the rate is proportional to the temperature.
d_ the rate is inversely proportional to the temperature.

20 when pink crystals of cobalt(ii) chloride are heated, steam is given off and the colour of the solid
changes to blue.
cocla*6h20 = cocl, + 6h20
what happens when water is added to the blue solid?
[coeur [ener |
a changes to pink decreases
b changes to pink increases
cc remains blue decreases
d remains blue increases

13 tthanol is used as a fuel.
ethanol + oxygen — carbon dioxide + water
which statements are correct?
1 the reaction is endothermic.
2 the products have more energy than the reactants.
3 the oxygen for this reaction comes from the air.
4 the temperature of the reaction mixture rises during this reaction.
a iand2 b 1and3 c 2and4 d 3and4

18 when pink crystals of cobalt(ii) chloride are heated, steam is given off and the colour of the solid
changes to blue.
coclz*6h20 = cocl2 + 6h20
what happens when water is added to the blue solid?
[tour [teers
a changes to pink decreases
b changes to pink increases
cc remains blue decreases
d remains blue increases

13 solid copper(ii) carbonate reacts with dilute sulfuric acid.
cuco3 + h2so4 — cuso, + coz + h20
the rate of the reaction can be changed by varying the conditions.
which changes always increase the rate of this chemical reaction?
1 increasing the concentration of sulfuric acid
2 _ increasing the size of the pieces of copper(ii) carbonate
3 increasing the temperature
4 increasing the volume of sulfuric acid
a 1,3 and 4 b 1tand3onlyy c 2and3 d 3 and 4 only

14 some changes are shown in the table.
in which rows are the changes described correctly?
| | chemical change physical change
1 rusting iron melting ice
2 burning ethanol evaporating ethanol
3 melting iron evaporating ethanol
4 cracking hydrocarbons burning methane
a 1and2 b 1and3 c 2and4 d 3and4

You're not logged in / signed up

It's free