chemistry

1 sodium chloride is a liquid at 900°c.
which row describes the arrangement and the motion of the particles in sodium chloride at 900°c?
arrangement motion
of particles of particles
a regular vibrate about a fixed point
b regular move randomly
cc random vibrate about a fixed point
d random move randomly

2 hydrogen chloride gas, hc/, reacts with ammonia gas, nh, to form solid ammonium chloride.
the apparatus is set up as shown.
after a few minutes, a white cloud of solid ammonium chloride forms where the two gases meet.
solid ammonium chloride
= ——
i i:
source of source of
hydrogen chloride gas ammonia gas
the experiment is repeated using hydrogen bromide gas, hbr, in place of hydrogen chloride.
how far along the tube does the white cloud of solid ammonium bromide form?
a b cc d
source of source of
hydrogen bromide gas ammonia gas

3 substances p and q both conduct electricity.

p is a mixture of two different types of atom.
q is made of only one type of atom.
which row describes p and q?

a alloy element

b alloy compound

cc compound alloy

d compound element

4 anatom of element r contains 15 protons, 16 neutrons and 15 electrons.
what is r?
a gallium
b_ phosphorus
c - sulfur
d= zinc

5 which molecule contains a double covalent bond between two atoms of the same element?
a carbon dioxide
b_ ethanol
c_ ethene
d nitrogen

6 — silicon(iv) oxide is a covalently bonded compound.
which statements are correct?
1 silicon atoms form four single bonds in silicon(iv) oxide.
2 oxygen atoms form two double bonds in silicon(iv) oxide.
3 silicondv) oxide has a high melting point.
4  silicon([v) oxide contains one silicon atom and four oxygen atoms.
a 1tand2 b 1and3 c 2and3 d 3and4

7 the equation for the reaction of iron(ii) oxide with carbon monoxide is shown.
fe,0, + 3co -— 2fe + 3cqo,
what is the percentage yield of iron when 16.8g of carbon monoxide reacts completely with
iron(ii) oxide to form 8.96 g of iron?
a 26.7% b 40.0% c 53.3% d 80.0%

8 whatis the volume of 14.5g of gaseous butane, c,h,,, at room temperature and pressure?
a 96.0cm° b 6.0cm* c 96.0dm° d 6.0dm°

9 aqueous copper(ii) sulfate is electrolysed using copper electrodes.
d.c. power
supply
copper +] l- copper
ad eeace

copper(ii) sulfate
which statement describes what happens during the electrolysis?
a copper atoms gain electrons at the cathode and copper(ii) ions lose electrons at the anode.
b_ electrons move in the external circuit from the positive electrode to the negative electrode.
c  copper(ii) ions move through the electrolyte from the cathode to the anode.
d copper is formed at the cathode and oxygen is formed at the anode.

10 electrolysis is carried out on concentrated aqueous potassium bromide using inert electrodes.
which products are formed at the anode and the cathode?
[wee [te
a bromine hydrogen
b bromine potassium
cc hydrogen bromine
d hydrogen potassium

11 hydrogen-—oxygen fuel cells and gasoline are each used to power cars.
which statement describes an advantage of using hydrogen—oxygen fuel cells in cars in comparison
with gasoline engines?
a_ hydrogen is a non-renewable resource.
b_ hydrogen is produced during the fractional distillation of petroleum.
c  hydrogen-oxygen fuel cells do not release carbon dioxide.
d  hydrogen—oxygen fuel cells need electricity to work.

12 plant cells use energy from sunlight for photosynthesis.
which row describes and explains the energy change that occurs?
type of explanation of energy change
energy change

a endothermic less energy is released making bonds than is
absorbed to break bonds

b endothermic more energy is released making bonds than is
absorbed to break bonds

cc exothermic less energy is released making bonds than is
absorbed to break bonds

d exothermic more energy is released making bonds than is
absorbed to break bonds

13 two different experiments are done to find the enthalpy change, ah, of each reaction.
the temperature of each reaction mixture is measured at the beginning of the reaction and after
3 minutes.
experiment 1 experiment 2
30 20 30 40
25 15 25 35
20 10 20 30
initial temperature temperature initial temperature temperature
ic after 3 minutes cg after 3 minutes
[°c °c
which row gives the correct sign for the value of ah for each experiment and identifies if the
reaction is endothermic or exothermic?
[seinen | eeeine
a | negative and endothermic positive and exothermic
b negative and exothermic positive and endothermic
c positive and endothermic negative and exothermic
d positive and exothermic negative and endothermic

14 the reaction pathway diagram for an endothermic reaction is shown.
u, vand ware known energy values.
7 a
roducts
f jeeecereseefereneren pp
energy
reactants
u aca es cdr occa
progress of reaction
which diagram shows the reaction pathway diagram when a catalyst is used in the reaction?
a b
v vv
energy | = / _____\_ products energy
reactants reactants
u wore nce c nee e cere nce ee: u fo 2 woo =~) ----- 2-2 --
products
progress of reaction progress of reaction
cc d
w ww
canesiiiinammens roducts roducts
soin ie pi a coe’ pi
energy energy
reactants reactants
u fiw 2 ee nee u ea ne eo eee = --
progress of reaction progress of reaction

15 which process is a physical change?
a burning a piece of magnesium
b_ reacting calcium carbonate with hydrochloric acid
c_ melting an ice cube
d the rusting of an iron nail

16 the contact process is used to convert sulfur dioxide to sulfur trioxide. vanadium(v) oxide is the
catalyst in this process.
2s0,(g) + 0,(g) = 280,(9)
the forward reaction in this equilibrium is exothermic.
which statements about this process are correct?
1 the catalyst increases the rate of both the forward and backward reactions.
2 a low pressure increases the yield of sulfur trioxide.
3 a low pressure is used to keep the costs low.
4 ahigh temperature increases the yield of sulfur trioxide.
a iand2 b 1and3 c 2and4 d 3and4

17 the equation for the decomposition of hydrogen peroxide, h,o,, is shown.
2h,0, — 2h,o0 + o,
in an experiment, the total volume of oxygen produced is 100 cm’.
the experiment is repeated using 1.00g of a solid catalyst. all other conditions remain the same.
which row describes the total volume of oxygen and the mass of the catalyst at the end of the
second experiment?
total volume of oxygen mass of catalyst
fom? ig

a more than 100 less than 1.00

b 100 less than 1.00

c 100 1.00

d more than 100 1.00

18 nitrogen reacts with hydrogen to form ammonia in the presence of an iron catalyst. the reaction
is reversible.
nj(g) + 3h,(g) = 2nh,(g)
which statement about this reaction is correct?
a the iron catalyst decreases the activation energy of only the forward reaction.
b when equilibrium is reached, the forward reaction has stopped.
c when the pressure changes, the concentration of ammonia at equilibrium remains constant.
d_ nitrogen and hydrogen never completely convert to ammonia.

19 the equation for a redox reaction is shown.
h,o, + 2ki + h,so, — i, + k,so, + 2h,o
potassium iodide is ...... 1 ...... agent in this reaction because iodide ions ...... 2 ...... electrons.
which words complete gaps 1 and 2?
_ | @¢ | # |
a an oxidising lose
b an oxidising gain
c a reducing lose
d a reducing gain

20 element e is in group ii of the periodic table.
which row describes element e and its oxide?
[even [ester

a metal acidic
b metal basic
c non-metal acidic
d non-metal basic

21  lead(ii) iodide is formed as a precipitate in the reaction shown.
pb(no3),(aq) + 2nal(aq) — pbli,(s) + 2nano,(aq)
which method is used to separate the lead(ii) iodide from the mixture?
a crystallisation
b distillation
c_ evaporation
d filtration

22 which statement explains why sulfur, s, has similar chemical properties to selenium, se?
a_ they both have the same number of electrons in their outer electron shell.
b_ they are both solids at room temperature and pressure.
c_ they are both non-metals.
d_ they both form negative ions.

23 atoms of sodium, rubidium and element q each have one outer shell electron.
some properties of these elements are shown.
diamant netting point boiling point density
in°c in °c in g/cm
sodium 98 883 0.97
rubidium 39 688 1.53
q 28 672 1.87
what is q?
a hydrogen
b lithium
c_ potassium
d caesium

24 which statement about elements in group viii of the periodic table is correct?
a they all have a full outer shell of electrons.
b_ they all react with group | elements to form ionic compounds.
c_ they are all diatomic molecules.
d_ they are all liquids at room temperature and pressure.

25 the electrical conductivity of magnesium is tested.
magnesium is then added to dilute sulfuric acid. a gas, w, is produced.
which row describes the electrical conductivity of magnesium and identifies w?
electrical conductivity gas w
of magnesium
a good hydrogen
b good oxygen
cc poor hydrogen
d poor oxygen

26 aluminium metal is extracted from its purified ore by electrolysis.
which statement about the electrolyte in this process is correct?
a_ the electrolyte is purified molten bauxite only.
b_ the electrolyte is purified bauxite dissolved in molten cryolite.
c_ the electrolyte is purified molten cryolite only.
d_ the electrolyte is purified cryolite dissolved in molten bauxite.

27 part of the reactivity series is shown.
potassium
xx
calcium
y
aluminium
which metals are represented by x and y?
p| ox ty
a copper magnesium
b sodium magnesium
cc sodium silver
d copper silver

28 some substances found in water extracted from a river are listed.
1 plastics
2 nitrates
3 oxygen
which substances are harmful to aquatic life?
a iand2 b 1and3 c 2only d 3only

29 car engines which use gasoline as a fuel produce oxides of nitrogen.
oxides of nitrogen are removed from the exhaust gases.
which statements about the formation or removal of oxides of nitrogen are correct?
1 gasoline reacts with nitrogen in the air to produce oxides of nitrogen.
2 gasoline contains nitrogen.
3 nitrogen and oxygen react at high temperatures to produce oxides of nitrogen.
4 nitrogen monoxide, no, reacts with carbon monoxide, co, in a catalytic converter.
a iand2 b 1and3 c 2and4 d 3and4

30 which structures represent a pair of structural isomers?
1 ch,ch,ch,ch,ch,ch,
2 ch,ch,ch,ch,ch(ch;),
3 ch,ch(ch3)ch,ch,ch,
4 ch,ch(ch,)ch,ch,ch,ch,
a iand2 b 1and3 c 2and4 d 3and4

31 alkanes are a homologous series of hydrocarbons.
the table shows the names and boiling points of the first four members of this series.
methane -162
ethane —89
propane -42
butane 0
pentane is the next member of the series.
which row gives the molecular formula and the boiling point of pentane?
|| molecular formula | boiling point/°c
a c5hi9 36
b c5h,. 51
cc coh 51
d c5h1. 36

32 which displayed formula represents the ester formed by the reaction of propan-1-ol with
ethanoic acid?
a b
ip il -
= ho oh ee i hoh oh
| \ | 1 1 | \ tot
me tt ce et tt
h h h h h h
cc d
il - ip
ope hoh vod hoh
| | \ tl | \ |
et met
h h h h

33 ethanol can be manufactured by fermentation and by the catalytic addition of steam to ethene.
which statement identifies an advantage of using one of these methods?
a_ catalytic addition requires a high temperature and pressure.
b_ ethanol produced by fermentation is extracted by distillation.
c_ fermentation is a batch process.
d_ the raw material in fermentation is a renewable resource.

34 which statement about carboxylic acids is correct?
a they react with alkalis to form a salt and water.
b_ they react with metals to form a salt and water.
c_ they react with metal carbonates to form a salt, water and hydrogen.
d_ the general formula for carboxylic acids is c,h.,,,oh.

35 the structure of a polymer is shown.
|
—n—-{_}-c—n—-{_}-c—
which statement about this polymer is correct?
a_ alkenes are polymerised to make the polymer.
b_itis a polyester.
c_ itis an addition polymer.
d_ water is produced when the polymer is made.

36 methane undergoes substitution reactions with chlorine and complete combustion with
excess oxygen.
which row about the two reactions is correct?
condition for . ;
‘ : ‘ equation for the complete combustion
reaction with chlorine
a an acid catalyst methane + oxygen — carbon dioxide + hydrogen
b an acid catalyst methane + oxygen — carbon dioxide + water
c ultraviolet light methane + oxygen — carbon dioxide + hydrogen
d ultraviolet light methane + oxygen — carbon dioxide + water

37 what is used to identify the end-point of an acid—base titration?
a balance
b~ measuring cylinder
c indicator
d_ volumetric pipette

38 four pure substances, p, q, r and s, are tested using chromatography. the same solvent is
used each time.
the table shows the distance moved by each substance and by the solvent from the baseline.
distance moved by | distance moved by
substance substance solvent
/com /cm

p 4.5 10.0

q 3.0 20.0

r 4.5 20.0

is} 13.5 30.0
which two substances are identical?
a pandr b pands c qandr d qands

39 a substance is tested with three different reagents.
which row shows the results obtained with aqueous iron(ii) nitrate?
aqueous acidified aqueous | acidified aqueous
sodium hydroxide silver nitrate barium nitrate
a green precipitate, no reaction no reaction
insoluble in excess
b green precipitate, white precipitate white precipitate
insoluble in excess
cc white precipitate, cream precipitate no reaction
insoluble in excess
d | white precipitate that no reaction white precipitate
dissolves in excess

40 a student carries out a flame test on a sample.
the flame colour observed is light green.
which ion is present in the sample?
a ba” b ca” c lit dk’

Solve 0620_s24_qp_23