chemistry

1 the diagram shows the boltzmann distribution of energies in a gas. the gas undergoes a
reaction with an activation energy, e,. the peak of the distribution is labelled p.
p
proportion of
molecules with
energy e i
0 i ;
0 e.
molecular energy, e
if the same reaction is carried out in the presence of a catalyst, which statement is correct?
a_ the peak p is at a lower height and the position of e, moves to the left.
b_ the peak p is at a lower height and the position of e, moves to the right.
c_ the peak p remains at the same height and the position of e, moves to the left.
d_ the peak p remains at the same height and the position of e, moves to the right.

2 diamond is a pure form of carbon. the mass of a diamond can be measured in carats. one carat
is 0.200 g of carbon.
which expression gives the number of carats that contain 6.02 x 107° carbon atoms?
a 0.200 x 12.0
bp 0.200
12.0
c 12.0
0.200
p 0.200 4420
6.02 x 1078

3 which molecule or ion contains the smallest bond angle?
a coh, b  ch;coch3 c nh. d nh;

4 four compounds are shown.
coh, c2hs0h ch3;cho ch3co2h
how many of these compounds have an odd number of o bonds?
a 1 b 2 cc 3 d 4

5  ethanal, ch3cho, ethanol, c2,h;0h, and methoxymethane, ch3ochs3, are three organic

compounds.
which compound has the highest boiling point and what is the interaction that causes this boiling
point to be the highest?

a methoxymethane permanent dipole-dipole forces

b ethanal hydrogen bonds

cc ethanol hydrogen bonds

d ethanal permanent dipole-dipole forces

6 what ts the oxidation number of sultur in eacn species ¢
/ [as [sos 480. |
a -2 +4 +4
b -2 +4 +6
cc +2 4 +4
d +2 4 +6

7 the following data are needed for this question.

ah? (n2h4(i)) = 50.6 kd mol

ah®(n20,(g)) = 9.2kj mol"

ah? (h,0(g)) = -241.8kj mol"
hydrazine, n2h,(i), reacts with dinitrogen tetraoxide, n2o,4(g), to form nitrogen gas and water
vapour.

2n2ha(l) + n2o4(g) > 3na(g) + 4h20(g)

what is the enthalpy change for this reaction?
a -1077.6kj mol"
b -856.8kj mol!
c -301.6kjmol*
d -182.0kj mor"

8 sodium burns in oxygen giving out heat energy and forming the compound na2o. the equation
for this reaction is shown.
2na(s) + $0,(g) > naz,o(s)
which statement about the reaction is correct?
a ah?° for the reaction is equal to twice the bond energy of the na—o bond.
b_ ah?® for the reaction is positive.
c_ the equation represents the standard enthalpy change of combustion of sodium.
d_ the equation represents the standard enthalpy change of formation of sodium oxide.

9 in the chemical equation, w, x, y and z are all whole numbers.
wclo; + xmno, + yh* — wclo, + xmno, + zh,o
when the equation is balanced, what are w, x and y?
po fw i x dy
a 4 1 2
b 2 2 2
cc 2 3 8
d 3 2 2

10 two compounds x and y react to produce compound z. the reaction is reversible.
x+ysez
when x and y are mixed together in a closed system a dynamic equilibrium is gradually
established.
which graph could represent the change in the rates of the forward and reverse reactions over
time?
a b
fs, % key
%, % rate of
me. 3 seseeeeeees forward
rate “seencccccccccccccccnce rate aa reaction
ee eee # *, %
pe ’ % rate of
?# e “ti \ ----- reverse
; 5 as reaction
0 time 0 time
cc d
ig f orm
* pd
*. % ¢
me *, ,
. . ¢
shy * ¢
*e. 7
rate see rate 4
7” rs,
, go
’ , ss
‘ , ts
4 ’ ms
, ’ "ag
0 time 0 time

11 the reaction between sulfur dioxide and oxygen is reversible.
2s0.(g) + o2(g) = 2s0;(g) k, = 280 mol" dm? at 1000k
in an equilibrium mixture at 1000k the sulfur dioxide concentration is 0.200 moldm™ and the
oxygen concentration is 0.100 moldm™.
what is the sulfur trioxide concentration?
a 1.058moldm?
b  1.120moldm®
c 2.366moldm®
d 5.600 moldm®

12 which oxide will cause an increase in ph when added to water?
a mgo b_ al,03 cc sio, d so,

13 x, y and z are consecutive elements in period 3 of the periodic table. element y has the highest
first ionisation energy and the lowest melting point of these three elements.
what are the identities of x, y and z?
pf x |v | 2 |
a na mg al
b mg al si
cc al si p
d si p is)

14 a 5.00g sample of an anhydrous group 2 metal nitrate loses 3.29g in mass when heated
strongly.
which metal is present?
a magnesium
b calcium
c strontium
d barium

15 solutions p and q each contain a different group 2 ion at the same concentration. one contains
mg”*, the other contains ba?*. tests are carried out on separate 5cm* samples of p and q.
test 1: add 1 cm® of 0.1 moldm™ nasso,(aq)
test 2: add 1. cm? of 0.1 moldm™ naoh(aq)
what are the results of these tests?
| resutsiniestt | esutsintest2
a more precipitate with ba?* more precipitate with ba2*
b more precipitate with ba”* more precipitate with mg**
cc more precipitate with mg?* more precipitate with ba2*
d more precipitate with mg?* more precipitate with mg?*

16 chlorine and bromine have different volatilities.
which row identifies the more volatile of the two elements, and gives the correct explanation?
identity of the explanation for the
more volatile element difference in volatility

a bromine instantaneous dipole-induced dipole forces
are greater in bromine than they are in chlorine

b bromine instantaneous dipole-induced dipole forces
are greater in chlorine than they are in bromine

cc chlorine instantaneous dipole-induced dipole forces
are greater in bromine than they are in chlorine

d chlorine instantaneous dipole-induced dipole forces
are greater in chlorine than they are in bromine

17 sodium azide, nansz, is dissolved in water. acidified silver nitrate is added to the solution and a
white precipitate forms. aqueous ammonia is then added to the white precipitate.
the azide ion, nz , has similar chemical properties to the cl ion.
which row of the table can be predicted from this information?
formula of observation on adding
white precipitate aqueous ammonia
a agn3 colourless solution formed
b agns precipitate remains
cc ag3n colourless solution formed
d ag3n precipitate remains

18 which type of reaction occurs when solid ammonium sulfate is heated with an excess of sodium
hydroxide solution?
a acid-base
b precipitation
c_ redox
d_ thermal decomposition

19 catalytic converters are fitted in the exhaust systems of many cars.
which gas:
e causes acid rain if it is released into the air
e is removed from car exhaust fumes by a catalytic converter?
a carbon dioxide
b_ carbon monoxide
c hydrocarbon vapour
d nitrogen dioxide

20 wvnich substance reacts with tricnioroetnene to give a chiral product?
a br b hcl c nacn d naoh

21 alkanes are saturated hydrocarbons.
which type of reaction are alkanes most likely to undergo?
a electrophilic addition
b _ electrophilic substitution
c_ free radical substitution
d nucleophilic addition

22 an alkene reacts with hot, concentrated, acidified potassium manganate(vii) to produce a single
organic product as shown.
hot, concentrated, oo oo
acidified kmno,(aq)
alkene ———____> oh
what is the structure of the alkene?
a b cc d

23 a tertiary bromoalkane, indicated here by >c-br, reacts with aqueous naoh. the mechanism
has the reaction pathway shown.
xx
sc-br + oh" y
energy
sc-oh + br-
progress of reaction
which point in the diagram is correctly identified?
a xis =c+
; \z 7
b xis —=
c yis =c+
\/ ~
d yis home br

24 bromoethane and chloroethane are added separately to water. hydrolysis reactions occur.
which compound hydrolyses more rapidly and what is the mechanism?
compound that ‘
f mechanism
hydrolyses more rapidly
a bromoethane electrophilic substitution
b bromoethane nucleophilic substitution
cc chloroethane electrophilic substitution
d chloroethane nucleophilic substitution

25 alcohol x is oxidised to form compound y.
ee composition of y is 54.54% carbon, 36.36% oxygen and 9.10% hydrogen. the m, of y is
what could be the structure of alcohol x?
a ch3ch2ch(oh)ch3
b  ch;ch2ch,ch2ch,0h
c ch3ch2ch2ch20oh
d ch3ch2ch(oh)ch2ch3

26 the diagram shows the structure of compound z.
zz
o oo
aw
what is the product of the reaction between compound z and an excess of nabh,?
a b cc d
oh oh oh oh oo o o oh

27 compound q shows the following reactions.

e it gives an orange precipitate with 2,4-dinitrophenylhydrazine.
e it gives a red-brown precipitate with fehling’s reagent.
e it gives a pale yellow precipitate with alkaline aqueous iodine.

what could be the identity of q?

a ethanal

b _propan-2-ol

c _propanal

d_propanone

28 tartaric acid, ho,cch(oh)ch(oh)coph, is found in many plants.
a sample of tartaric acid reacts with an excess of lialh, to form the organic product j.
what happens when naoh(aq) is added to separate samples of tartaric acid and j?
a both tartaric acid and j react.
b_ only tartaric acid reacts.
c only j reacts.
d_ neither tartaric acid nor j react.

29 vhen ch2(onh)ch=chco>h is warmed wiin a little concentrated sulfuric acid, a cyclic compound
is formed.
what is the skeletal formula of the cyclic compound?
a b cc d
o [@)
no ‘0 | |
—
oo
(@) oo

30 the infra-red spectrum of compound p is shown.
100
transmittance
'% 50
0
4000 3000 2000 1500 1000 500
wavenumber/cm-'
what could be compound p?
a methyl ethanoate
b _propanal
c_propanoic acid
d_propan-2-ol

31 a particular atom of germanium, ge, has a nucleon number of 70.
which statements about a 22ge atom are correct?
1 it has the same number of electrons as a 2? se2* ion.
2 it has the same number of neutrons as an atom of $8zn.
3 it has half as many protons as an atom of ‘gd.

32. the first ionisation energy of chlorine is greater than that of sulfur.
which factors contribute to this?
1. chlorine has more protons in its nucleus than sulfur does.
2 chlorine has greater electron shielding than sulfur does.
3. the covalent bonds in chlorine molecules are stronger than those in sulfur molecules.

34 the stoichiometry of a catalysed reaction is shown by the equation below.
p(g) + q(g) = rig) + sil)
two experiments are carried out in which the amount of r is measured. the results are shown in
the diagram.
experiment 1
amount experiment 2
of r
0
0 time
which changes in the conditions could explain the results shown?
1 a lower pressure was used in experiment 2.
2  adifferent catalyst was used in experiment 2.
3 product s was continuously removed from the reaction vessel in experiment 2.

35 which statements are correct?
1. chloride ions are oxidised when concentrated sulfuric acid is added to nacl(s).
2  adisproportionation reaction takes place when chlorine is added to cold naoh(aq).
3. anacidic solution forms when chlorine is added to water.

36 nitrogen gas is unreactive, whereas oxygen gas and chlorine gas are reactive.
which statements help to explain this difference?
1 the two n atoms in an nz molecule are held together by a very strong triple bond.
2 the triple bond between two n atoms is not polar. the bonds in o2 and clz are polar.
3 the atoms in nz have a full outer shell of electrons. the atoms in o2 and cl2 do not have a
full outer shell of electrons.

37 the structure of tiglic acid is ch3ch=c(ch3)co2h.
which statements about the properties of one molecule of this acid are correct?
1 it contains two x bonds.
2 it contains four lone pairs of electrons.
3 it has all its atoms in the same plane.

38 which compounds, on heating with an excess of concentrated sulfuric acid, produce only one
product with molecular formula c7h19?
1 2 3
oh
oh
. oh |
oh oh oh

39 hydrogen cyanide reacts with propanone in the presence of potassium cyanide.
which statements about this reaction are correct?
1 the cyanide ion is a catalyst for the reaction.
2 this is an addition reaction.
3. the intermediate behaves as a base.

1 the diagram shows a boltzmann distribution of the energies of gaseous molecules and the

activation energies, e,, of a reaction with and without a catalyst.

proportion of

molecules

with energy, e

0 “~~
0 ex e.,
molecular energy, e

which statement about this distribution curve is correct?
a if the temperature of the gas is increased, the maximum of the curve becomes higher.
b _ if the temperature of the gas is increased, the maximum of the curve moves to the left.
c_ the fraction of molecules that react in the presence of a catalyst is shown by za
d_ the fraction of molecules that react in the absence of a catalyst is shown by ni

2 in this question it snould be assumed that (nh4)2z2co3.a20(s) dissolves in water without causing
an increase in volume.
which mass of (nh4)2co3.h20(s) should be added to 800 cm? of water to form a 0.100 mol dm™
solution of nh,* ions?
a 4.56g b_ 7.13g c 9.12g d 143g

3 the graph shows the successive ionisation energies of element x and element y.

both elements are in period 3.

f key

i ------- element x

energy : — element y
012 3 4 5 6 7 8 9g 10
successive
ionisation energies
which statement is correct?
a anatom of element x needs one extra electron for a full outer shell; an atom of element y
needs three extra electrons for a full outer shell.

b- anatom of element y has five electrons in the 3p subshell.
c_ element x has an oxidation number of +7 in most of its compounds.
d_ when element x combines with element y, the bonding is ionic.

4 which statement about the electrons in a ground state carbon atom is correct?
a_ electrons are present in four different energy levels.
b_ there are more electrons in p orbitals than there are in s orbitals.
c_ the occupied orbital of highest energy is spherical.
d_ the occupied orbital of lowest energy is spherical.

2 inthis question you snould assume the vapour behaves as an ideal gas.
0.175g of a volatile liquid produces a vapour of volume 4.50 x 10~°m* at 100°c and pressure of
1.013 x 10°pa.
what is the m, of the liquid?
a 31.9 b 87.1 cc 119 d 127

6 which reaction is endothermic?
a ca(oh)2(aq) + 2hcl(aq) - cacl2(aq) + 2h20(i)
b 2cl(g) > cl2(g)
c 2ca(s) + ong) > 2cao(s)
d caco,(s) > cao(s) + co2(g)

7 which equation correctly represents the standard enthalpy change of atomisation of the given
element?
a 719) > ig)
b_ na(s) > na(g)
c clg) > 2cl(g)
d na(g) > na‘(g) + &

8 (nh,)2cr207 decomposes when heated.
(nh4)2cr207 — no + 4h20 + cro3

which element is oxidised and which element is reduced?
[| enaied | reeveoe |

a chromium nitrogen

b hydrogen chromium

cc nitrogen chromium

d nitrogen hydrogen

9 when lead(ii) sulfide, pbs, is heated in air, sulfur dioxide and lead(ii) oxide are formed.
what is the equation for the reaction between pbs and oxygen?
a pbs + 202 > soz + pboz
b pbs + 240, > so; + pbo;
c pbs + 140, > so, + pbo
d pbs + 202 + so; + pbo

10 the decomposition of so3(g) is a dynamic equilibrium.
2s03(9) == 2s02(g) + o2(9)
what happens when the pressure of the system is increased?
a_ the rate of reaction will decrease and the position of the equilibrium will move to the left.
b_ the rate of reaction will decrease and the position of the equilibrium will move to the right.
c_ the rate of reaction will increase and the position of the equilibrium will move to the left.
d_ the rate of reaction will increase and the position of the equilibrium will move to the right.

11. hydrated aluminium ions undergo the following reaction.
[al(h2o)6]**(aq) + h2o(l) == [al(h2o)soh]?*(aq) + h30*(aq)
which statement about this reaction is correct?
a h,0(l) and [al(h,0);oh]**(aq) are a conjugate acid-base pair.
b_h20(!) is acting as an acid as it is donating h” ions.
c_ if oh (aq) is added, the equilibrium will move to the right.
dk, varies as the ph is varied.

12 which diagram correctly shows the electronegativity of the elements na, mg, al and si plotted
against their first ionisation energies?
a b
si si
© (}
al al

13 which statement about the compounds of group 2 elements magnesium to barium is correct?
a_ carbonates of group 2 elements produce bubbles when added to dilute nitric acid.
b_ nitrates of group 2 elements produce nitrogen and oxygen on heating.
c oxides of group 2 elements produce bubbles when added to dilute hydrochloric acid.
d_ the oxides of group 2 elements are amphoteric.

14 when equal volumes of saturated solutions of barium hydroxide and calcium hydroxide are
mixed, a white precipitate, y, forms. the mixture is filtered and carbon dioxide is bubbled through
the filtrate, producing a second white precipitate, z.
what are y and z?
y z

a ba(oh)2 ca(oh).

b ba(oh)> caco;

cc ca(oh) baco3

d ca(oh). ba(oh).

15 chlorate(v) ions, clo3, are produced in the redox reaction between chlorine and hot aqueous
sodium hydroxide. oxidation numbers can be used to help balance the equation for this reaction.
vcl2(g) + woh (aq) > xcl(aq) + yclo3 (aq) + zh2o(l)
what are the values of v, x and y in the balanced equation?
pot ow | x | oy |
a 2 3 1
b 3 4 2
cc 3 5 1
d v 12 2

16 the properties of chlorine, bromine and their compounds are compared.
which property is smaller for chlorine than for bromine?
a __ bond strength of the hydrogen-halide bond
b first ionisation energy
c solubility of the silver halide in nh3(aq)
d _ strength of the van der waals’ forces between molecules of the element

17 solid sodium iodide reacts with concentrated sulfuric acid to form more than one product that
contains sulfur.
what is the lowest oxidation number of sulfur in these products?
a -2 b o c +4 d +6

18 which emission from an internal combustion engine contributes to the erosion of marble statues?
a carbon monoxide
b_ nitrogen
c nitrogen dioxide
d_unburnt hydrocarbons

19 ammonia, carbon dioxide and water react together to form ammonium carbonate.
which statement about this reaction is correct?
a itis a redox reaction.
b_itis an acid-base reaction.
c the h—-n-h bond angle decreases as a consequence of this reaction.
d_ the three substances react in a 1:1:1 ratio in this reaction.

20 structural isomerism and stereolsomerism should be considered when answering this question.
how many isomers with the formula cs5h1o have structures that involve z bonding?
a 3 b 4 cc 5 d 6

21 the diagram shows the skeletal formula of phenazine.
n
ss
clo
n
phenazine

what is the empirical formula of phenazine?
a ceh,4n b  cehen c  cr2hsn2 d  cy2hy2no2

22 an organic compound x reacts with hot, concentrated acidified potassium manganate(vii)
solution to give a single carbon-containing product.
what could be x?
a ch2c(chs)2
b  ch3chchchs
c ch2chch2ch3
d ch3ch2ch2ch3

23 1-chloro-2-methylbutane reacts with sodium cyanide in ethanol in a nucleophilic substitution
reaction.
what is the most likely intermediate or transition state in this reaction?
a b
h p ~ h;c, ti ~
= =
ch(ch,)ch,ch, ch,
cc d
h;c, po h wa
tc +c
ch, ch(ch,)ch,ch,

24 propan-1-ol can be reacted with acidified potassium dichromate(vi) to form propanoic acid,
reaction 1, or propanal, reaction 2.
oo oo
i reaction 1 reaction 2 i
ch,ch,coh ~——— _ ch,ch,ch,oh ————* ch.ch,ch
propan-1-ol
how can the reaction be carried out to ensure that reaction 2 occurs rather than reaction 1?
a anexcess of acidified potassium dichromate(v1) is used.
b_ anexcess of concentrated sulfuric acid is added.
c_ the reaction mixture is distilled immediately after mixing.
d_ the reaction mixture is heated under reflux.

25 what is the smallest amount of oxygen molecules needed for the complete combustion of 40.0g
of methanol?
a 1.88 moles b 2.50 moles c 3.75 moles d_ 5.00 moles

26 compound x has stereoisomers and forms a precipitate when warmed with fehling’s reagent.
what could be the structure of compound x?
a b cc d
(e)
o (6) (6)

27 the diagram shows the structure of y.
h h h
or es
rile
two suggestions are made about y.
1 yan be oxidised by hot, acidified dichromate(vj) ions.
2 one mole of y gives one mole of tri-iodomethane when it reacts with an excess of
alkaline aqueous iodine.
which suggestions are correct?
a both 1 and 2
b 1 only
c 2only
d_ neither 1 nor 2

28 esters can be prepared by the reaction of a carboxylic acid with an alcohol in the presence of
concentrated sulfuric acid.
which row gives the correct names of the reagents that would be suitable to prepare ester z?
zz
o
feta
alcohol carboxylic acid
a butan-1-ol methyl propanoic acid
b propan-1-ol butanoic acid
[e propan-2-ol butanoic acid
d propan-2-ol propanoic acid

29 compound q can be hydrolysed by hc/(aq). ihe two products of this hyarolysis nave the same
empirical formula.
what could q be?
a  ch3co2ch2ch20oh
b ch3co,ch2ch2co2h
c ch3ch2co2ch2ch2ch3
d ch3ch2ch(oh)ch(oh)ch2ch3

30 substance t was analysed and found to contain 62.07% carbon, 10.34% hydrogen and
27.59% oxygen.
the infra-red spectrum of substance t is shown.
100
transmittance
'% 50
0
4000 3000 2000 1500 1000 500
wavenumber/cm=
which substance could be t?
a b cc d

31 which gaseous molecules are polar?
1. ammonia
2 hydrogen sulfide
3 boron trifluoride

32 a carbon monoxide molecule, co, has three bonds between the carbon atom and the oxygen
atom.
which features are present in one co molecule?
1 two lone pairs of electrons
2  aco-ordinate (dative covalent) bond from oxygen to carbon
3 two zm bonds

33 carbon can exist as allotropes which include graphite, diamond and a fullerene.
which statements are correct?
1 all three allotropes contain covalent bonds.
2. all three allotropes are giant molecular.
3. all three allotropes have delocalised electrons.

34 the reaction pathway diagram for a reversible reaction is shown.
50
energy
/kj mor"
20
progress of reaction
which statements are correct?
1. the enthalpy change for the backward reaction is -20kj mol.
2 the forward reaction is endothermic.
3 the activation energy for the forward reaction is +70 kj mol.

35 silicon forms a tetrachloride, sic14.
which statements are correct?
1 = in sicl4, the si is 5+ and each clis 5-.
2 ~ sicl, is a liquid at room temperature.
3. sicl, reacts with water to give an acidic solution and a precipitate.

36 which statements about ammonia are correct?
1. anammonia molecule has three bond pairs and one lone pair of electrons.
2 when ammonia is bubbled into water the ph of the solution increases.
3 ammonia gas can be made by warming ammonium sulfate with aqueous hydrochloric acid.

37 following fractional distillation of crude oil, which processes can be used to produce propene
from larger hydrocarbon molecules?
1 cracking
2. reduction
3. polymerisation

38 bromoethane undergoes nucleophilic substitution reactions.
which statements are correct?
1 bromoethane reacts with aqueous naoh to make ethanol.
2  bromoethane reacts with ethanolic nh3 to make ethylamine.
3 bromoethane reacts with ethanolic kcn to make ethanenitrile.

39 which reagents, when used in excess, can convert y into z?
ch3ch(oh)co2h -> ch3ch(oh)co2na
y z
1 na
2 nasco;
3 naoh

40 each of the compounds below is treated separately with an excess of nabhy,.
the product of each reaction is then heated with an excess of concentrated h2sox..
which compounds give only one final product with the molecular formula c7h19?
1 2 3
oo
o
/ ; / °
[e) h (e) h [e) h

Solve 9701_w19_qp_11