chemistry

1 element x has six more protons than element y.
which statement must be correct?
a atoms of element y are smaller than atoms of element x.
b_ element x has a full shell of electrons.
c_ element x and element y are in the same group.
d_ element x and element y are in the same period.

2 which statement explains why calcium has a higher melting point than barium?

a calcium cations are smaller than barium cations and have a stronger attraction to the
delocalised electrons.

b_ the structure of calcium is partly giant molecular.

c_ there are more delocalised electrons in calcium than in barium as it has a lower ionisation
energy.

d_ there is greater repulsion between barium atoms as they have more complete electron
shells than calcium atoms.

3. three statements about potassium and chlorine and their ions are listed.
1 the atomic radius of a potassium atom is greater than the atomic radius of a chlorine
atom.
2 the first ionisation energy of potassium is greater than the first ionisation energy of
chlorine.
3. the ionic radius of a potassium ion is greater than the ionic radius of a chloride ion.
which statements are correct?
a 1only b  2only c 1and3 d 2and3

4 for which equilibrium do both of the equilibrium constants k, and k, have no units?
a h,(g) + l(g) = 2hi(g)
b n,(g) + 3h,(g) = 2nh,(g)
c n,0,(g) = 2no,(g)
d so0,(g) + $0,(g) = so,(g)

5 calcium carbide, cac,, reacts with water, as shown. the data below the equation show, in kj mol,
the standard enthalpies of formation of the compounds involved.
cac js) + h,o(l) — cao(s) + c,h,(g)
-—60 —286 —635 +228
what is the standard enthalpy change of the reaction shown?
a -753kjmol™
b -61kjmol™
c +61kjmol’
d +753kjmol"

6 in the sodium chloride lattice the number of chloride ions that surround each sodium ion is called
the coordination number of the sodium ions.
what are the coordination numbers of the sodium ions and the chloride ions in the sodium chloride
lattice?
coordination number | coordination number
of sodium ions of chloride ions

a 4 6

b 6 4

cc 6 6

d 8 6

7 — histidine is an amino acid.
histidine
h 2
hsh
we il p
h nn
~n~ noo
\ /{/ in n
c==n h h o—h
f
h
what are the approximate bond angles 1, 2, and 3?
pt: | 2 fe |
a 109.5° 107° 90°
b 120° 107° 109.5°
cc 120° 120° 90°
d 120° 120° 109.5°

8 the contact process takes place at a pressure between 100000 pa and 200000 pa. a catalyst is
used.
which statement is correct?
a_ av,o, catalyst is added to increase the equilibrium yield of the reaction.
b_ changes in pressure have no effect on the position of equilibrium.
c_ the equilibrium yield of the reaction is very high under the conditions used.
d_ aniron catalyst is added to increase the rate of reaction.

9 bromine reacts with aqueous sodium hydroxide at 25 °c.
reaction 1 br,(aq) + 2naoh(aq) — nabr(aq) + naobr(aq) + h,o(i)
the naobr formed is unstable at 25 °c and reacts further.
reaction 2 3naobr(aq) - 2nabr(aq) + nabro,(aq)
which reactions are disproportionations?
a both reaction 1 and reaction 2
b_ neither reaction 1 nor reaction 2
c_ reaction 1 only
d_ reaction 2 only

10 which statement is correct?
a the relative atomic mass of a *°clatom is 35.5.
b_ the relative formula mass of caco, is 100.1.
c_ the relative isotopic mass of a 4g atom is 24.3.
d_ the relative molecular mass of o, is 16.0.

11 lodine and propanone react according to the following equation.
i,(aq) + ch3;coch,(aq) — ch,;coch,i(aq) + hi(aq)
if the concentration of propanone is increased, keeping the total reaction volume constant, the
initial rate of the reaction also increases.
what could be the reason for this?
a agreater proportion of collisions are successful at the higher concentration.
b_ the particles are further apart at the higher concentration.
c_ the particles have more energy at the higher concentration.
d_ there are more collisions per second between particles at the higher concentration.

12 four successive ionisation energies (ie) of element e are shown.
element e is in period 3 of the periodic table.
fifth ie sixth ie seventh ie eighth ie
/kj mol /kj mol /kjmot' /kjmot
16000 20000 24000 29000
in which group of the periodic table is e?
a 14 b 15 cc 16 d 17

13 in this question you should assume that the gas formed behaves as an ideal gas.
a 1.7g sample of mg reacts with 50.0 cm? of 2.2moldm™* hclat 303k and 110400 pa.
which volume of gas is produced, measured under these conditions?
a 1.3dm° b 1.6dm° c 2.5dm° d 5.0dm°

14 chlorine dioxide, c1o,, reacts with aqueous sodium hydroxide to produce water and a mixture of
two sodium salts, naclo, and nac1o3.
what is the mole ratio of nac/o, to nac1o, in the product mixture?
a 1:2 b 3:5 c 1:1 d 5:3

15 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 higher energy?
number of molecules with the number of molecules with
most probable energy higher energy

a decreases decreases

b decreases increases

c increases decreases

d increases increases

16 for which compound is there the greatest percentage loss of mass on strong heating?
a anhydrous calcium carbonate
bs anhydrous calcium nitrate
c anhydrous magnesium carbonate
d anhydrous magnesium nitrate

17 the solids sodium chloride and sodium iodide both react with concentrated sulfuric acid at room
temperature.
with nacl, the products are nahso, and hcl.
with nal, the products are nahso,, hi, i,, so,, h,o, s and h,s.
what is the explanation for this difference in products?
a_ chloride ions will displace iodine from the solution.
b_ hydrogen chloride is more volatile than hydrogen iodide.
c __lodide ions are better reducing agents than chloride ions.
d_ sulfuric acid is able to act as a dehydrating agent with nal.

18 sio, has a melting point of 1713 °c. it reacts with hot naoh(aq) to form sodium silicate, na,sio3,
and water.
no reaction occurs when sio, is added to hot h,so,(aq).
what can be deduced from this information?
chemical structure
behaviour of sio, of sio,
a amphoteric giant
b amphoteric simple
c acidic giant
d acidic simple

19 element x has the second largest atomic radius in its period. an atom of x has three occupied
electron shells only.
the oxide of x is shaken with water.
what could be the ph of the resulting solution?
a 5 b 7 c 9 d 14

20 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

21 the diagram shows the melting points of eight elements with consecutive atomic numbers.
which element could be sodium?
d
melting
point/k
cc
a
b
atomic number

22. the boiling points of br, ic/ and ibr are given in the table.
ee
which row explains:
¢ — why the boiling point of ic/is greater than br,
¢ — why the boiling point of ibr is greater than ici?
boiling point of iclis boiling point of ibr is
greater than br, greater than ici
a | iclhas stronger instantaneous | ibr has stronger instantaneous
dipole-induced dipoles dipole-induced dipoles
b icl has permanent dipoles ibr has stronger instantaneous
dipole-induced dipoles
c | iclhas stronger instantaneous ibr has stronger
dipole-induced dipoles permanent dipoles
d ic/ has permanent dipoles ibr has stronger
permanent dipoles

23 a solution contains both mg*"(aq) and sr**(aq) at the same concentration.
the solution is divided into two equal portions. aqueous sodium hydroxide is added dropwise to
one portion. dilute sulfuric acid is added dropwise to the other portion.
which row is correct?
precipitate seen first precipitate seen first
when naoh(aq) is added | when h,so,(aq) is added

a magnesium hydroxide magnesium sulfate

b magnesium hydroxide strontium sulfate

c strontium hydroxide magnesium sulfate

d strontium hydroxide strontium sulfate

24 structural isomerism and stereoisomerism should be considered when answering this question.
if a molecule contains two non-identical chiral carbon atoms, four optical isomers exist.
how many isomers are there with:
¢ molecular formula c7h,,o and
¢ a five-membered ring and
¢ —atertiary alcohol group?
a 4 b 5 cc 9 d 13

25 which reagent will react with pentan-3-ol to give a mixture of stereoisomers?
a acidified potassium dichromate
b_ concentrated sulfuric acid
c_ ethanoic acid in the presence of a little concentrated h,so,
d hydrogen chloride

26 anorganic molecule w contains 3 carbon atoms. it requires 4.5 molecules of oxygen for complete
combustion.
what could w be?
a propane
b _propanoic acid
c_propanone
d_propan-1-ol

27 which equation represents a reaction that proceeds through initiation, propagation and termination
steps?
a cyhyg + cl, > c,h gcl + hcl
b- c,;h,,br + naoh — c,h,,oh + nabr
c c,h, + ho > c,h,,0h
d c,h,;cho + hcn - cgh,,ch(oh)cn

28 structural isomerism and stereoisomerism should be considered when answering this question.
a set of isomeric hydrocarbons:
* all contain 14.3% by mass of hydrogen
¢ all react with bromine by addition, 0.280 g of each hydrocarbon reacting with 0.799 g of
bromine.
what is the maximum number of isomeric compounds in the set?
a 1 b 3 cc 4 d 5

29 which row describes the solvent used and type of reaction occurring when bromoethane reacts
with naoh to form ethene?
a ethanol elimination
b ethanol substitution
c water elimination
d water substitution

30 which row describes the type of reaction that occurs when propan-1-ol reacts to form the named
carbon-containing product?
[ catonconannanoac [ypecacton
a 1-chloropropane addition to propan-1-ol
b carbon monoxide complete combustion of propan-1-ol
c propene dehydration of propan-1-ol
d propanal reduction of propan-1-ol

31 which statement describes what happens when 2-chloro-2-methylpropane is warmed with
naoh(aq)?
a_ this secondary halogenoalkane reacts by a mixture of an sy1 and an sy2 mechanism.
b_ this secondary halogenoalkane reacts only by an s,2 mechanism.
c this tertiary halogenoalkane reacts mostly by an s,1 mechanism.
d this tertiary halogenoalkane does not react with hydroxide ions under these conditions.

32 how many structurally isomeric secondary alcohols are there with the molecular formula c;h,,0?
a 1 b 2 cc 3 d4

33 which reagent:
* can confirm the presence of a carbonyl group in an organic compound
e does not distinguish between aldehydes and ketones?
a acidified k,cr,0,
b  2,4-dnph reagent
c_ fehling’s reagent
d liaih,

34 which compound gives a positive test with alkaline aqueous iodine and does not show optical
isomerism?
a  ch;,coch,ch,oh
b  ch,ch,ch(oh)cho
c ch,coch(oh)ch,
d  (ch3),c(oh)cho

35 two samples of compound x were treated separately with different reagents which were added in
excess.
the products of these two reactions are shown.
oh o
oh
reaction 1
ala a e)
(6)
compound x oh oh
reaction 2 aaan
oh
which reagents could be used for reaction 1 and reaction 2?
see tn
a | hot acidified sodium dichromate(vi) na
b | hot acidified sodium dichromate(vi) nabh,
c |tollens’ reagent followed by hcl(aq) na
d | tollens’ reagent followed by hcl(aq) nabh,

36 which method could produce butanoic acid?
a anacid—base reaction involving ch;ch,ch,co,na
b the hydrolysis of ch,ch,ch,ch,cn
c the acidic hydrolysis of ch;ch,cooch,ch,ch,
d the oxidation of ch;ch,ch,0h

37 which ester may be hydrolysed to produce two products, one of which may be reduced to the
other?
a  ch,ch,co,ch,
b  ch,ch(ch3)co,ch,ch(ch;),
c ch,ch,co,ch(chs),
d (ch,),chco,ch(ch,),

38 two compounds, x and y, are mixed and a little concentrated h,so, is added.
ester z is found in the resulting mixture of products.
ester z
of
o
fe) l e
a, fe)
which two compounds could be x and y?
pt ty
a ch,ch,oh ch(co,h),
b ch3;ch,oh = | chz,co,ch,ch(oh)ch,ococh,ch,
cc ch,co,h ch,ch,co,ch,ch(oh)ch,0oh
d ch,co,h ch,(oh)ch(oh)ch,(oh)

39 the diagram shows a section of a polymer molecule.
—ch,-ch=ch-ch,—ch,—ch=ch-ch,—
which monomer will produce this polymer?
a ch,=ch,
b  ch,ch=ch,
c ch,ch=chch,
d ch,=ch-ch=ch,

40 there are two naturally occuring isotopes of bromine. one isotope has 44 neutrons. the other
isotope has 46 neutrons.
ignoring fragments, how many peaks are there in the mass spectrum of tribromomethane, c'hbr,?
a 2 b 3 cc 4 d 6

Solve 9701_s23_qp_11