chemistry

1. the temperature of a sample of an inert gas is increased.
what effect does this have on the number of molecules with the most probable energy and on the
number of molecules with high energy?
number of molecules with number of molecules
the most probable energy with high energy
a decreases decreases
b decreases increases
cc increases decreases
d increases increases

2 a -sample of element x is analysed using mass spectrometry. the mass spectrum obtained is
shown.
56%
41%
% abundance
3%
112 113 114 115 116
mile
what is the relative atomic mass of this sample of element x?
a 113.7 b 114.0 c 114.2 d 114.4

3 a washing powder contains sodium hydrogencarbonate, nahcos, as one of the ingredients.
in a titration, a solution containing 1.00g of this washing powder requires 7.15cm?* of
0.100 moldm™ sulfuric acid for complete reaction. the sodium hydrogencarbonate is the only
ingredient that reacts with the acid.
what is the percentage by mass of sodium hydrogencarbonate in the washing powder?
a 3.0% b 6.0% c 12.0% d 24.0%

4 the outermost electron in an atom of neon occupies a particular orbital.
which row shows the relative energy and shape of this orbital?
ce

a higher or equal
b higher or equal @)
c lower or equal
d lower or equal q

5 in which species is there a lone pair of electrons?
a ch; b ch3* c ch; d ch,

6 when an evacuated tube of volume 400cm°” is filled with gas at 300k and 101 kpa, the mass of
the tube increases by 0.65g.
assume the gas behaves as an ideal gas.
what could be the identity of the gas?
a argon
b helium
c_ krypton
d neon

7 under which conditions will nitrogen behave most like an ideal gas?
[ [temperate [pressure _|
a low high
b high low
cc low low
d high high

8 two reactions and their enthalpy changes are shown.
2c(s) + 2h2(g) > c2ha(g) ah® = +52.2kj mol"
coh2(g) + ho(g) > coha(g) ah°=-175.8kj mol
these data can be used to calculate the enthalpy change for the reaction shown.
2c(s) + h2(g) > czh2(g)  ah°=x
what is the value of x?
a -228.0kj mol"
b -123.6kj mol
c +123.6kjmol™
d +228.0kjmol*

9 ethanedioic acid, hozcco2h, can be oxidised by kmno, in dilute sulfuric acid. the products of
this reaction are carbon dioxide, water, potassium sulfate and manganese(ii) sulfate.
in this reaction each ethanedioic acid molecule loses two electrons as it is oxidised. a
half-equation for this process is shown.

ho2cco2h + 2co2 + 2h* + 2e7

how many water molecules are produced when five ethanedioic acid molecules are oxidised by
kmn0o, in dilute sulfuric acid?
a 5 b 8 cc 10 d 16

10 hydrogen iodide gas decomposes reversibly producing iodine vapour and hydrogen.
2hi(g) == i2(g) + he(g) ah = +12kjmol"
the position of the equilibrium for this reaction may be altered by changing the external
conditions.
which row correctly describes the change in position of equilibrium?
[ace [a
the pressure the temperature

a moves to the right moves to the right

b moves to the right moves to the left

cc no change moves to the right

d no change moves to the left

11 the reaction between sulfur dioxide and oxygen is reversible.
2s0,(g) + o2(g) == 2s03(g) ke = 280 mol dm? at 1000k
in an equilibrium mixture at 1000 k the sulfur trioxide concentration is 6.00 moldm~.
the sulfur dioxide concentration is twice the oxygen concentration.
what is the sulfur dioxide concentration?
a 0.175moldm*
b 0.254 moldm®
c 0.318moldm®
d 0.636 moldm®

12 1.15g of a metallic element needs 300cm” of oxygen for complete reaction, under room
conditions, to form an oxide which contains o* ions.
what could be the identity of this metallic element?
a calcium
b magnesium
c_ potassium
d_ sodium

13 the relative melting points of four consecutive elements in the periodic table are shown in the
graph.
the elements all have proton numbers less than 20.
which element is in group 16?
a
melting
point/k
b c
213 aparna ee gee
d
proton number

14 substance x reacts with water. a gas is given off and the ph of the solution increases. the

solution is then reacted with sulfuric acid and a white precipitate forms.
what could be substance x?
a barium
b barium oxide
c magnesium
d magnesium oxide

ee

15 solutions of 0.1moldm™ mg(no3)2 and 0.1moldm™ ba(no3)2 separately undergo a series of
reactions using pure reagents.
sodium
carbonate excess hcl(aq) excess
solution then boil naoh(aq)
mg(no;),(aq). ——————* _m —————_> n —————* p
sodium
carbonate excess hcl(aq) excess
solution then boil naoh(aq)
ba(no,),(aq) ———————_> q ————> r ———> §$
m, n and p are magnesium compounds.
q, r and s are barium compounds.
how many of m, n, p, q, r and s are white precipitates?
a 2 b 3 cc 4 d 5

16 concentrated sulfuric acid is added to separate solid samples of sodium chloride, sodium
bromide and sodium iodide.
with which samples does sulfuric acid act as an oxidising agent?
a __ sodium chloride only
b sodium chloride and sodium bromide
c_ sodium bromide and sodium iodide
d _ sodium iodide only

17 the reaction of bromine with warm naoh(aq) produces products with the same oxidation
numbers, in the same ratios, as the reaction of chlorine with hot naqh(aq).
in one reaction between bromine and warm naoh(aq), 30.2g of a product containing sodium,
bromine and oxygen is produced.
which mass of naoh has reacted?
a 8.00g b 10.2g c 20.3g d 48.0g

18 at 550°c nitrogen dioxide reacts with unburnt hydrocarbon fragments such as chs in the
catalytic converter of a motor vehicle.
4ch; + 7no2 > 34n, + 4co2z + 6h20
which row gives the energy change for this reaction and a possible reason for it?
energy change reason why the reaction is endothermic
of reaction or exothermic
a endothermic chemical energy is converted to heat energy
b endothermic the n=n bond energy is very high
cc exothermic co, and h20 have negative ah? values
d exothermic double bonds are broken in no2

19 which statement is correct?
a ammonia reacts with alkalis to form the ammonium ion.
b ammonium chloride contains ionic, covalent and co-ordinate bonds.
c the ammonium ion reacts with acids to produce ammonia.
d_ the bond angle in the ammonium ion is approximately 107°.

20 the diagrams show two different compounds.
ss sa
1 2
what is
e the total number of structural isomers, including compound 2, that could be formed
by adding a second methyl group to the ring of compound 1,
e the number of x electrons in each compound?
number of number of
isomers m electrons
a 3 2
b 3 4
cc 5 2
d 5 4

21 which compound has the molecular formula cgh1;,0?
a b cc d
(@)
0 [@)
oh

22 what is the structural formula of the major product when hydrogen bromide reacts with
2-methylbut-2-ene?
a ch2brch(ch3)ch2ch3
b  (chs3)2cbrch2chs
c (ch3)2chchbrchs
d (ch3)2chch,ch2br

23 which reaction is most likely to involve the formation of a positively charged intermediate?
a 1-bromopentane and warm dilute naoh(aq)
b 1-bromo-2,2-dimethylpropane and warm dilute naqh(aq)
c  1-bromo-3-methylbutane and warm dilute naoh(aq)
d = 2-bromo-2-methylbutane and warm dilute naoqh(aq)

24 the infra-red spectrum of a substance with empirical formula c2h,o is shown.
100
transmittance
50
0
4000 3000 2000 1500 1000 500
wavenumber/cm
which bonds are responsible for peak x and peak y?
[pea peak
a c-h c=c
b c-h c=o
cc o-h c=c
d o-h c=o

25 the structure of coniine is shown.
coniine
our
it
coniine can be synthesised by reacting ammonia with a dibromo compound, x.
nh3 + cghiebr2 > coniine + 2hbr
xx

what is the name of compound x?

a 1,1-dibromo-2-propylcyclopentane

b1,2-dibromo-2-propylcyclopentane

c_1,4-dibromooctane

d_1,5-dibromooctane

26 structural isomerism and stereoisomerism should be considered when answering this question.
3-methylhexan-3-ol reacts with hot, concentrated sulfuric acid to form several isomeric
compounds with the molecular formula c7h 44.

3-methylhexan-3-ol

a
how many isomeric compounds could be formed in this reaction?
a 3 b 4 cc 5 d 6

27 anorganic compound t undergoes the following reactions.

et is oxidised by hot, acidified potassium manganate(vii).
e t reacts with sodium to give hydrogen.

what could be compound t?

a ch3ch2ch(oh)ch3

b  ch;ch2,ch,cho

c (ch3);coh

d ch3;ch2coch3

28 compound x is treated with two reagents successively, forming compound z.
xx
cho a mild
oxidising
agent nabh,
a scuy > 7
coch,
what could be z?

a b cc d
co,h ch,oh ch,oh co,h

29 which reagent may be used to distinguish between propanone and ethanol?
a 2,4-dinitrophenylhydrazine
b_ bromine water
c_ febhling’s reagent
d_ tollens’ reagent

30 which compound is chiral?
a 1-chloro-3-methylbutane
b= 2-chloro-2-methylbutane
c  2-chloro-3-methylbutane
d  3-chloropentane

31. anatom of calcium-48 can form a 2+ ion.
which statements about this ion are correct?
1. it has 20 protons.
2 it has 28 neutrons.
3 it has 22 electrons.

32 four elements, w, x, y and z, have electronic configurations as shown.
2.6.8.1
which formulae represent compounds that have boiling points below room temperature?
1 wx,
2 yx
3 zx

33 which statements about enthalpy changes are correct?
1. the enthalpy change of atomisation is always positive.
2 ~the enthalpy change when a c-c bond is broken is positive.
3. the enthalpy change of neutralisation of a weak acid is always negative.

34 vanadium and pepsin can both act as catalysts. vanadium is a metal. pepsin is an enzyme.
which statements are correct for both vanadium and pepsin?
1. they will speed up any chemical reaction.
2 they can lower the activation energy for a reaction.
3. they are not used up when they act as catalysts.

35 which oxides, when placed in cold water for one day, will react with the water?
1. mgo
2 = alzo3
3 sio,

36 a mixture of magnesium carbonate and magnesium nitrate is heated strongly in a hard-glass
test-tube.
which gases are formed?
1 carbon dioxide
2 nitrogen dioxide
3 oxygen

37 which statements about poly(alkene)s are correct?
1 poly(alkene)s do not react with br2(aq) in the dark.
2 disposal of poly(alkene)s by combustion can produce harmful products.
3. poly(alkene)s do not readily biodegrade.

38 compound y
e reacts with alkaline aqueous iodine to form a yellow precipitate
e changes the colour of warm, acidified potassium dichromate(vj) solution.
what could be compound y?
oh
ai
[e)
2 i
h
: a
(e)

39 carboxylic acids can be made by several different reactions.
which statements are correct?
1. the acid hydrolysis of ch;ch2cn will make ethanoic acid.
2 ~the oxidation of ch3ch2ch2ch2oh will make butanoic acid.
3 the oxidation of ch3;ch2cho will make propanoic acid.

40 carboxylic acids react with alcohols to produce esters.
carboxylic acid x forms one ester only with molecular formula c5h1.o2.
what could x be?
1 ethanoic acid
2. propanoic acid
3. butanoic acid

Solve 9701_s19_qp_11