chemistry

1 the mass spectrum of a sample of neon is shown. the relative abundance of each peak is
written in brackets above it.
(100)
relative
abundance
(8)
(0.3)
20 21 22
mass
charge
what is the relative atomic mass, a,, of this sample of neon?
a 20.15 b 20.20 c 21.00 d 21.82

2 2.q0g of ammonium nitrate, nngno3, decomposes to give 0.90 g of water and a single gas.
what is the identity of the gas?
a no b no, c no d ne

3 which of these elements has the highest fifth ionisation energy?
a c bn cc p d si

4 the ion x™ has the same electronic configuration as the atom kr.
what is the electronic configuration of an atom of x?
a [ar]4s73d'°4p®
b [ar]4s*3d'°4p°5s?
cc [ar]4s74d'°4p°
d  [ar]4s*4d'°4p°5s?

5 which type of interaction exists between water molecules and metal cations in aqueous solution?
a dipole-dipole interactions
b_ hydrogen bonds
c__ion-dipole interactions
d_ ionic bonds

6 which substance snows the greatest deviation trom the properties of an ideal gas under room
conditions?
a co,(g) b_ hg) c ne(g) d  nh3(g)
lee aaa. as a.

7 in order to determine the enthalpy of neutralisation of a strong acid and a strong alkali, 25.0 cm”
of 2.00 moldm™® sodium hydroxide is added to 25.0 cm? of 2.00 mol dm™® hydrochloric acid. the
increase in temperature is 12°c.

in a second experiment, the same method is used, but 50.0 cm? of 2.00moldm~?
sodium hydroxide is added to 50.0 cm? of 2.00 mol dm hydrochloric acid.

what is the increase in temperature in the second experiment?

a 6°c b 12°c c 24°c d 48°c

8 which equation represents the enthalpy change of atomisation of iodine?
a lg) > ig)
b_ 1g) > 21(g)
cc f1,(s) > ig)
d_ i,(s) > 2i1(g)
ee

9 zinc atoms can be oxidised to zn“ ions by dichromate(vi) ions in acid solution. chromium is
reduced to cr* in this reaction.
which equation is correct?
a cr07* + zn + 14h* > 2cr** + zn** + 7h2o
b cr,0,7 + zn + 14h* > 2cr** + 3zn?* + 7h,o
c cr0,* + 3zn + 14h* > 2cr** + 3zn** + 7h2o
d 2cr,0,* +3zn + 14h* > 2cr** + 3zn** + 7h2o

10 the equation shows that h2(g) and i,(g) react to form an equilibrium mixture.
h2(g) + l(g) = 2hi(g) ah® = -9.6kj mol
a mixture containing equal amounts of h2(g) and i,(g) is made at temperature 7, and the
composition of the mixture is monitored. a graph of the results is shown.
0.5
mole fraction
of 1,(9)
0,23 -p2-sc5=->>
0
0 time
the experiment is repeated at a lower temperature, to.
which new graph would be obtained?
a b
ob} al

11 the diagram shows the boltzmann distribution of energies for a reactant gas. for a particular
reaction, the activation energy is x.
number of
particles with :
energy, e
0 '
0 xx
energy, e
which change to the diagram occurs if an effective catalyst is added at the same temperature?
a more particles will possess higher values of e.
b_ the peak will move to the left.
c_ the peak will move to the right.
d_ the value of the activation energy decreases.

12 which element requires the least number of moles of oxygen for the complete combustion of
1 mol of its atoms?
a aluminium
b magnesium
c_ phosphorus
d_ sodium

13 an element, y, reacts according to the following sequence.
burns an excess of
in o, hcl(aq) naoh(aq) naoh(aq)
y ——— white solid ———— solution ————~ white precipitate ——————— solution
what could be element y?
a na b mg c al dp

14 in which list are all three compounds soluble in water?
a barium chloride, calcium carbonate, magnesium hydroxide
b _ barium hydroxide, calcium hydroxide, strontium carbonate
c barium chloride, barium hydroxide, magnesium sulfate
d barium sulfate, calcium sulfate, magnesium hydroxide

15 anhydrous magnesium nitrate, mg(no3)2, decomposes when heated, giving a white solid and a
mixture of two gases, x and y.
y is oxygen.
what is the ratio mass of x released 5
mass of y released ©
a —1- b —1_ c —1l p
0.174 0.267 0.348 3.43

16 inaseries of nine experiments, to test the reactivity of the halogens, an aqueous solution of each
halogen is added to an equal volume of an aqueous solution containing halide ions, as shown in
the table.

halogen halide solution
solution sodium chloride (aq) | sodium bromide (aq) | sodium iodide (aq)
chlorine (aq) experiment 1 experiment 2 experiment 3
bromine (aq) experiment 4 experiment 5 experiment 6
iodine (aq) experiment 7 experiment 8 experiment 9
the nine resulting mixtures are then shaken separately with an equal volume of hexane. the nine
tubes are left to stand so that the aqueous and organic solvents separate into layers.
how many test-tubes contain a purple upper hexane layer?
a 1 b 2 cc 3 d 5

17 zisacompound of sodium, chlorine and oxygen.
it contains 45.1% by mass of oxygen.
z is prepared by reacting sodium hydroxide with chlorine.
which row shows the conditions used for the reaction and the oxidation state of chlorine in z?
|_| reaction conditions | oxidation state of clin z_|
a cold dilute naoh +1
b cold dilute naoh +5
cc hot concentrated naoh +1
d hot concentrated naoh +5

18 which row is correct?
a te [os
molecule ion molecule ion
a pyramidal regular tetrahedral o o
b pyramidal regular tetrahedral o t
cc regular tetrahedral pyramidal o o
d regular tetrahedral pyramidal t o

19 the table describes two possible environmental consequences of adding too much ammonium
nitrate fertiliser to the soil.
which row is correct?
increased plant photochemical
growth in rivers smog
a x x
b v x
cc x v
d jv v

20 hex-2-ene can be made by the reaction shown.
f yok ho
wx a ees
gi

which statement about this reaction is correct?

a (ch3)3co” is behaving as a br@nsted-lowry base.

b  (chs3)3co™ is behaving as an oxidising agent.

c_ the c-i bond breaks via homolytic fission.

d_ this is a hydrolysis reaction.

21 structural isomerism only should be considered when answering this question.
molecule x contains three c=c double bonds. one mole of x is reacted with three moles of hbr.
the carbon skeleton is unchanged.
molecule x
own
how many different products are formed?
a 3 b 4 cc 6 d 8

22 structural isomerism and stereoisomerism should be considered when answering this question.
a colourless liquid, cs5h;,cl, exists as a mixture of two optical isomers.
when heated with sodium hydroxide in ethanol, a mixture of only two alkenes is formed.
what could the colourless liquid be?
a (ch3ch2)2chc1
b  ch3;ch,ch2chcich3
c chsch2cci(chs)2
d  (chs)2chchcich3

23 when 2-bromo-2-methylpropane reacts with aqueous sodium hydroxide, an alcohol is formed.
which diagram describes the first step in the reaction mechanism?
a b cc d
ch, ch, ch, ch,
ot nolo ot nota
\~ | _/ acl
ch, ch, ho: ch, ho: ch,

24 when an organic compound, q, is treated with phosphorus pentachloride, fumes of hydrogen
chloride are evolved. when q is warmed with acidified aqueous potassium dichromate(vi), the
solution turns green.

what is q?

a ch3ch2,cho

b  ch3;ch2co2h
c chsch(oh)ch3
d (chs)s;coh

25 alcohol y gives a yellow precipitate with alkaline aqueous iodine. it can be oxidised to give a
mixture of products including substance z. substance z gives a red-brown precipitate with
fehling’s solution.

which alcohol could be y?

a  ch3ch(oh)ch(ch3)ch20h
b  ch3c(oh)(ch3)ch2ch20h
c chsch(oh)ch2ch(oh)ch3
d  ch2(oh)ch2ch(oh)ch2ch3

26 chsch2zcoch2ch; reacts with hydrogen cyanide to form an organic product called a
cyanohydrin.
which statement is correct?
a the cyanohydrin product has one chiral centre.
b_ the cyanohydrin product is formed by electrophilic addition.
c_ the cyanohydrin product is formed via an intermediate which contains a c-oh group.
d_ the formation of the cyanohydrin product requires the use of cyanide ions as a catalyst.

2/ leaduction of compound r with lialh, gives the compound 4-meiny!pentane-2, 3-diol.
what could be the identity of compound r?
a b cc d
aa [e) o (6) o o
sor an vx

28 citric acid is found in lemon juice.
citric acid
ho,cch2c(oh)(co2h)ch2co2h
which volume of 0.40moldm™ sodium hydroxide solution is required to neutralise a solution
containing 0.0050 mol of citric acid?
a 12.5cm3 b  25.0cm* c 37.5cm* d 50.0cm*

29 the structural formula of an ester is (ch3)2choco(ch2)2ch3.
this ester is boiled with aqueous hydrochloric acid.
which two products are formed?
a _propan-1-ol and butanoic acid
b_propan-2-ol and butanoic acid
c_propan-1-ol and propanoic acid
d_propan-2-ol and propanoic acid

30 the infra-red spectra of three organic compounds are shown.
100
transmittance /%
spectrum 1 50
0
4000 3000 2000 1500 1000 500
wavenumber /cm-'
100
transmittance /%
spectrum 2 50
0
4000 3000 2000 1500 1000 500
wavenumber/cm™
100
transmittance /%
spectrum 3 50
0
4000 3000 2000 1500 1000 500
wavenumber/cm='
what could the three compounds be?
[| spearumt | specrum2 [spectrums |
a propanoic acid propanone propan-2-ol
b propanone propanoic acid propan-2-ol
cc propanone propan-2-ol propanoic acid
d propan-2-ol propanoic acid propanone

31 which changes can be used to measure the rates of chemical reactions?
1 the decrease in concentration of a reactant per unit time
2 the rate of appearance of a product
3. the increase in total volume of gas per unit time at constant pressure

32. iron reacts with steam to produce hydrogen and an oxide of iron.
3fe(s) + 4h20(g) = fe30.(s) + 4h2(g)
a system containing all four substances is at equilibrium.
which changes will decrease the mass of fe present at equilibrium?
1 addition of steam at constant pressure
2 __ increase in overall pressure
3 addition of an effective catalyst

33 ethylene glycol, hoch2ch20oh, is used as a de-icer. it allows ice to melt at temperatures
below 0°c.
which statements are correct?
1 ethylene glycol disrupts the extensive network of hydrogen bonds in ice.
2. ethylene glycol molecules form hydrogen bonds with other ethylene glycol molecules.
3. ethylene glycol molecules will dissolve in the water formed from the ice.

34 which molecules contain at least one unpaired electron?
1 no
2 noz
3 nhs3

35 which elements form a chloride in which both covalent bonding and coordinate (dative covalent)
bonding are present?
1 al
2 = si
3 mg

36 which statements about calcium oxide are correct?
1 it can be reduced by heating with magnesium.
2 itis produced when calcium nitrate is heated.
3 it reacts with cold water.

37 adiketo acid is a compound with two ketone groups and one carboxylic acid group.
limonene terpinolene

which statements about the reactions of limonene and terpinolene are correct?

1. when reacted with an excess of hydrogen and a nickel catalyst, limonene and terpinolene
produce the same compound.

2  anexcess of hot concentrated acidified kmno, reacts with limonene and with terpinolene to
form different diketo acids.

3. the reactions of limonene and terpinolene with an excess of br. produce positional isomers
with the same number of chiral carbon atoms.

38 one molecule of dodecane, c12h2¢, is cracked, producing three product molecules, x, y and z.
x is a straight chain alkane. y and z are straight chain alkenes with different m, values.
which statements about x, y and z are correct?
1 if y and z are but-1-ene and ethene respectively, x will be hexane.
2 ‘if x is butane, then y and z could both show cis-trans isomerism.
3. xcould be octane.

39 which statements about chlorofluoroalkanes are correct?
1. both the c-cl and c-f bonds are readily dissociated by ultra-violet light.
2 they have caused ozone depletion.
3. they are relatively chemically inert.

40 which reactions of propan-1-ol have water as one of the products?
1 passing propan-1-ol vapour over hot al203
2. mixing propan-1-ol with warm ethanoic acid and a few drops of concentrated sulfuric acid
3. warming propan-1-ol with hbr

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