chemistry

1. in which carbon allotrope are all electrons localised?
a __ buckminsterfullerene
b~ diamond
c graphite
d graphene

2  acopper ore contains 3.00% of copper carbonate, cucq3, by mass.
which mass of copper would be obtained from 1 tonne of the ore?
a 1.91kg b 3.71kg c 15.4kg d 58.4kg

3 the catalysed formation of ammonia by the haber process can be represented by the equation
shown.
n2(g) + 3h2(g) == 2nh3(g) ah = -92kj mol"
which change in conditions will increase both the rate of formation and the equilibrium yield of
ammonia?
a decrease in the temperature
b increase in the temperature
c increase in the pressure
d increase in the surface area of the catalyst

4 solid sulfur consists of ss molecules.
which equation represents the standard enthalpy of atomisation of sulfur?
a 4s2(s) > s(g)
b 38g) > s(g)
c s,(s) > 8s(g)
d ss(g) > 8s(g)

5 in this question you should use changes in oxidation numbers to balance a chemical equation.
the following reaction occurs when mno; is warmed with dilute h2sox.
amnoz + bh* > cmn* + dmno, + eh,0
what is the ratio of c : din the correctly balanced equation?
a 1:1 b 1:2 c 2:3 d 3:2

6 in this question you should assume air contains 21% oxygen.
what is the minimum volume of air required to ensure complete combustion of 10cm? of butane
gas, under room conditions?
a 14cm° b 27cm c 65cm* d 310cm*

7 when aqueous bromine is shaken with cyclohexane and allowed to stand, two layers form. the
top cyclohexane layer is coloured and the bottom aqueous layer is almost colourless.
what is the most likely explanation for this observation?
a_ bromine is reduced to bromide ions in the bottom layer.
b- bromine molecules are non-polar.
c_ bromine reacts with water but cannot react with cyclohexane.
d_ the product of the reaction between bromine and cyclohexane is coloured.

8 in which change are only temporary dipole-induced dipole forces overcome?
a czhsoh(l) - c2hsoh(g)
b  h,0(s) > h20(1)
c o,(s) > o2(i)
d = cahro(!) > cahio(s)
ie eee

9 the complete combustion of 2 moles of an alkane produces 400 dm” of carbon dioxide measured
at 301k and 1 x 10°pa. carbon dioxide can be assumed to behave as an ideal gas under these
conditions.

what is the formula of the alkane?
a cghig b cyeh34 cc coh a2 d cuohge

10 in which reaction does an element undergo the largest change in oxidation number?
a cl, + 20h — oci” + cl’ + h,0
b 3cl, + 6oh — clo; + 5ci + 3h20
c cr0,* + 6fe* + 14h* — 2cr** + 6fe* + 7h2o
d 3mno,2 + 4h* -» mno, + 2mno, + 2h,o

11 pcl; decomposes as shown.
pcls(g) = pcl3(g) + cl2(g)
1.0mol of pcls(g), 1.0mol of pcl3(g) and 1.0mol of cl2(g) are placed in a container of volume
1dm*® at 250°c and allowed to reach equilibrium.
at this temperature, the equilibrium mixture contains 1.8 moles of pcl3.
what is the value of k, at 250°c?
a 1 b 1.8 c 9 d 16.2

12 the fifth to eighth ionisation energies of four elements in period 3 of the periodic table are
shown.
which row refers to chlorine?
ionisation energies /kj mol
a 6280 21200 25900 30 500
b 6990 8490 27100 31700
cc 6540 9330 11000 33600
d 7240 8790 12000 13800

13 magnesium nitrate, mg(no3)2, decomposes when heated to give a white solid and a mixture of
gases. one of the gases released is an oxide of nitrogen, x.
7.4g of anhydrous magnesium nitrate is heated until no further reaction takes place.
what mass of x is produced?
a 1.5g b 2.3g c 3.0g d 46g

14 which statement explains why iodine is less volatile than chlorine?
a chlorine is more electronegative than iodine and so has more repulsion between its
molecules.
b_ the greater number of electrons in iodine leads to larger temporary dipole-induced dipole
forces.
c_ the i-i bond energy is smaller than the c/—cl bond energy.
d_ the iodine molecules have stronger permanent dipole-permanent dipole forces.

15 ammonium carbonate is a crystalline solid. on gentle warming a reaction occurs, forming
ammonia as one product.
how are the carbonate ions behaving during this reaction?
a_ br@nsted-lowry acid
b_br@nsted-lowry base
c_ oxidising agent
d_ reducing agent

16 one molecule of an oxide of element z reacts with six molecules of water to produce an acidic
compound.
what is element z?
a aluminium
b_ phosphorus
c . silicon
d © sulfur

17 which property shows an increase from magnesium to barium?
a the first ionisation energy of the elements
b the oxidising power of the metals
c the solubility of the hydroxides
d the solubility of the sulfates

18 a test-tube of hbr(g) and a separate test-tube of hi(g) are heated to the same temperature.
which combination of observations is possible?
[| estuseorrera) [teste oth)
a a brown vapour appears no change
b a purple vapour appears no change
cc no change a brown vapour appears
d no change a purple vapour appears

19 most modern cars are fitted with catalytic converters in the exhaust system.
which three gases are removed by a catalytic converter?
a carbon monoxide, hydrocarbons, nitrogen oxides
b_ carbon monoxide, carbon dioxide, nitrogen oxides
c carbon monoxide, nitrogen oxides, sulfur dioxide
d hydrocarbons, nitrogen oxides, sulfur dioxide

20 compound x is shown.
compound x
co,h
oh
x is treated separately with naoh(aq) and lia/h, to give y and z.
co,h
naoh(aq) lialh,
¥ = ——_————— ———— z
oh
what are y and z?
ee ee ee
co,na ch,oh
oh oh
co,na co,h
oh oh
co,na ch,oh
,
ona oh
co,na co,h
ona oh

21 the table shows the molecular formulae of three molecules p, q and r. none of the molecules
are cyclic.
molecular formula

p ch,o0

q ch202

r ch20
which molecules show a strong absorption between 1610cm™ and 1750cm™ in their infra-red
spectra?
a qonly b~ ronly c qandronly d p,qandr

22 which row correctly shows the type of mechanism of each of the two reactions?
[gers ken | oc00r fen
a electrophilic substitution electrophilic addition
b electrophilic substitution nucleophilic addition
cc nucleophilic substitution electrophilic addition
d nucleophilic substitution nucleophilic addition

23 ester x is shown.
ester x
ch3co2(ch2)7ch3
ester x is hydrolysed using aqueous sodium hydroxide.
what is the molecular formula of one of the products?
a c2h,o2 b  c,h30.na c cghig0 d  cgh,7o2na

24 which reagent could be used to distinguish between propane-1,2-diol and ethane-1 ,2-diol?
a alkaline aqueous iodine
b aqueous acidified dichromate(v1)
c_ ethanol and a few drops of concentrated sulfuric acid
d_ sodium metal

25 which substance forms propanoic acid as one of the products when it reacts with hot
concentrated acidified potassium manganate(vii)?
a but-1-ene
b _but-2-ene
c 2-methylpropene
d  2-methylbut-1-ene

26 the structure of damascenone is shown.
damascenone
[e)
oe
including damascenone, how many stereoisomers exist with this structural formula?
a 1 b 2 cc 4 d 8

27 how many isomeric esters have the molecular formula c4hgo2?
a 2 b 3 cc 4 d 5

28 ethene reacts with aqueous bromine to give two products, ch2brch2br and ch2zbrch20n.
which statement about these products is correct?
a_ both products are obtained in this reaction by nucleophilic substitution.
b_ both products are obtained in this reaction by nucleophilic addition.
c_ both products can be hydrolysed to form the same organic compound.
d both products can form hydrogen bonds with water.

29 pvc is used as a packaging material.
what holds the different polymer strands together in a piece of solid pvc?
a covalent bonds
b_ hydrogen bonds
c_ ionic bonds
d_ van der waals’ forces

30 the diagram shows the structure of buta-1,3-diene.
buta-1 ,3-diene
iol
ge ly el ty ot
hood

the addition reaction between buta-1,3-diene and two molecules of hydrogen bromide can
produce three structurally isomeric products.
how many of these products have at least one chiral centre?
a 0 b 1 cc 2 d 3

31 scientists are trying to synthesise a new element with proton number 119. the element is
predicted to be a group 1 element in period 8 of the periodic table.
which predictions are likely to be correct about this element?
1. the outermost occupied orbital of one atom of this element will be an s orbital.
2 the atomic radius will be the largest of the seven elements in group 1.
3 it will have a greater first ionisation energy than element 118.

32 which reactions would have the reaction profile shown?
energy |
progress of reaction
1 naoh + hcl > nacl + h,0
2 caco; > cao + co,
3  2mgo > 2mg + o2

33 which factors can lead to an increase in the rate of a reaction?
1 alower activation energy
2 _anincrease in temperature
3 anincrease in the concentration of a reactant

34 sodium and fluorine are both reactive elements. two atoms are described.
ee
atomic number 9 11
nucleon number 19 23
which statements about these two atoms, and the ions they can form, are correct?
1 one na atom has two more protons than one f ion.
2 one na atom has two more neutrons than one f atom.
3 one na’ ion has the same number of electrons as one f7 ion.

35 in the atmosphere, which transformations can involve sulfur dioxide as either a reagent or a
catalyst?
1 no, tono
2 no to no2
3  coto co

36 the bond ......p...... of the hbr molecule is ......q...... than that of the hi molecule.
which pairs of words correctly complete the above sentence?
energy greater
length less
polarity greater

37 compound x has the structure shown.
compound x
oh
ay
which statements about compound x are correct?
1. xwill decolourise cold, acidified kmno,(aq).
2  xgives an orange precipitate with 2,4-dnph reagent.
3  x does not react with tollens’ reagent.

38 propanal reacts with hydrogen cyanide.
which absorptions are present in the infra-red spectrum of the product?
1 aweak absorption in the range 2200-2250 cm"
2  astrong absorption in the range 3200-3600 cm
3 astrong absorption in the range 1040-1300 cm"

39 which alcohols cannot be dehydrated to form alkenes?
1 ch3;0h
2  (ch3)3coh
3 =ch3ch(oh)chs

40 areaction mechanism is shown.
h,c —— \ h,c _
me in - me /" + br
hc fe h,c _ wi
ho- 4 oh
which statements about this reaction are correct?
1. heterolytic bond fission occurs.
2 ‘it is a substitution reaction.
3 oh behaves as an electrophile.

Solve 9701_s20_qp_12