chemistry

1. which particle has equal numbers of protons and neutrons and an electronic structure of
1872s?2p°3s73p°?
a 33ar b 3ca** c %or d #s

2 which molecule contains six bonding electrons?
a ncl3 b hs c coh,4 d sf.

3 solid carbon dioxide, coz, is similar to solid iodine, iz, in its structure.
which statement about solid co2 and solid sioz is correct?
a both solid coz2 and solid sio> exist in a lattice structure.
b_ both solid co2 and solid sioz have a simple molecular structure.
c_ both solid coz and solid sioz have atoms joined by single covalent bonds.
d_ both solid coz and solid sio2 change spontaneously to gas at s.t.p..

4 the enthalpy changes of two reactions are shown.
k2co3(s) + 2hcl(aq) > 2kcl(aq) + h2o(i) + co.(g) ah =-34.0kjmol™
khco(s) + hcl(aq) > kcl(aq) + h2o(l) + co.(g) ah =+32.8kjmol'
what is the enthalpy change for the reaction shown?
2khco3(s) > k2co3(s) + h20(i) + co2(g)
a -31.6kjmol*
b  1.2kjmol*
c 66.8kjmol™
d 99.6kjmol"

5 nitrogen reacts with oxygen to form nitrogen monoxide, no, and nitrogen dioxide, noz. nitrogen
dioxide reacts with water and with hydroxide ions.
n2(g) + o2(g) > 2no(g)
2no(g) + o2(g) > 2no2(g)
2no.(g) + h2o(i) - hno2(aq) + h*(aq) + nos; (aq)
2no.(g) + 2oh (aq) — noz (aq) + no3 (aq) + h20(i)
what can be deduced using only the information from these equations?
a hnopis a strong acid.
b  hnos is a weak acid.
c nodzis aneutral gas.
d nois areducing agent.

6 which solution has the lowest ph value?
a_ 0.01 moldm butanoic acid
b 0.01 moldm’ ethanoic acid
c 0.01 moldm® hydrochloric acid
d 0.01 moldm® sulfuric acid

8 whatis the electronic configuration of an isolated ni”* ion?
a 1s?2s72p°3s73p°3d°4s7
b_ 1s72s72p°3s3p°3d’4s'
c  1s72s?2p°3s?3p°3d'°4s"
d  1s72s?2p°3s3p°3d®

9 at200°c aluminium chloride is a gas with m, = 267.
what is the number of covalent bonds, dative covalent bonds and lone pairs of electrons in one
molecule of aluminium chloride at 200°c?
covalent dative jone waa
bonds covalent bonds pals

a 6 2 0

b 6 2 16

cc 6 2 18

d 3 0 9

10 when solid kc/oq, is heated in the absence of air, a mixture of two chlorine compounds in the
mole ratio of 3:1 is formed. chlorine is the only element whose oxidation number changes in this
reaction.

what could be the oxidation numbers of chlorine in the two compounds that are formed?
a +3 and-1 b +6 and +4 c +7 and -1 d +7 and +1

11 two reactions are shown.
reaction 1 x2(g) + yo(g) = 2xy(g)
reaction2 xy(g) = $x.(g) + 4y2(g)
the equilibrium constant, kp, for reaction 1 is 0.0052.
what is k, for reaction 2?
a 26x 10° b 13.9 c 192.3 d 384.6

12 compound t is a white crystalline solid.
when a sample of compound t is mixed with aqueous sodium hydroxide and heated, a gas is
produced which turns damp red litmus paper blue.
further testing of a solution of compound t with aqueous barium chloride produces a dense
white precipitate which does not dissolve when dilute hydrochloric acid is added to the mixture.
what is the identity of compound t?
a ammonium carbonate
b ammonium sulfate
c sodium carbonate
d sodium sulfate

13. which property explains the trend in volatility of the elements going down group 17?
a decreasing covalent bond strength
b_ decreasing van der waals’ forces
c_ increasing covalent bond strength
d increasing van der waals’ forces

14 the statements apply to the elements in group 2.
which statement is correct?
a_ as atomic number increases, ionic radius increases.
b_ as atomic number increases, reducing ability decreases.
c_ as atomic number increases, first ionisation energy increases.
d_ asatomic radius increases, first ionisation energy increases.
eee

15 which element, when burned in oxygen, can form an oxide that is a reducing agent?
a na b mg cc al ds

16 nitrogen oxides are removed from the exhaust gases of internal combustion engines by the
action of a catalyst in a catalytic converter.
which row is correct?
change in oxidation
| number of nitrogen ype ef catalyst
a decrease heterogeneous
b decrease homogeneous
cc increase heterogeneous
d increase homogeneous

17 the addition of aqueous silver nitrate to aqueous barium chloride produces a white precipitate
which dissolves in an excess of dilute aqueous ammonia to form a colourless solution.
the addition of an excess of dilute nitric acid to the colourless solution produces a white
precipitate, z.
what is z?
a agcl b_ bacl, c ba(nos)2 d nh,no;

18 which property shows an increase from calcium to barium going down group 2?
a_ the ease of decomposition of the carbonates
b the solubility of the hydroxides
c the solubility of the sulfates
d_ the volume of hydrogen given off when 1g of the metal reacts with water

19 element x is in period 3. it reacts rapidly with water to form an alkaline solution.
which statement about the chloride of element x is correct?
a it conducts electricity when molten.
b_ it has a melting point of less than 100°c.
c_ithas covalent bonding.
d_ it reacts rapidly with cold water.

20 structural and stereoisomerism should be considered when answering this question.
when trans-pent-2-ene reacts with hbr, how many different products can form?
a 1 b 2 cc 3 d 4

21 ester p has the following structural formula.
ester p
(e)
oak
\
och,ch,ch(ch,),
which compounds are produced when p is hydrolysed using dilute hydrochloric acid?
a ch3coci and (ch3)2chch2ch20h
b  ch3ch20h and (ch3)2z,chch2co2h
c chs3co2h and (ch3)2,chch2co2h
d chs3coh and (ch3)2,chch2ch20h

22 i|here are many non-cyciic alcohols that cannot be oxidised by warm acidified mnq, ions.
alcohol x is the member of this set of alcohols with the lowest molecular mass.
how many moles of oxygen are required for the complete combustion of 1.0 mol of alcohol x?
a 3.5mol b 4.5mol c 6.0mol d- 6.5mol

23 butanoic acid can be produced from 1-bromopropane in two steps using reagents v and w as
shown.
reagent v reagent w
1-bromopropane ———————— compound q ———————» butanoic acid

what could be reagents v and w?
ee ee ee ee

a kcn in ethanol hcl(aq)

b kcn in ethanol naoh(aq)

cc nhs in ethanol hcl(aq)

d naoh(aq) h*/cr207* (aq)

24 which statement about compound t and compound u is correct?
compound t compound u
o o
a | ned
\ %
ch,ch,ch, ch(ch,)ch,ch,
a t and u are stereoisomers.
bt can be distinguished from u by the use of alkaline aqueous iodine.
ct can be reduced by liazh, but not by nabh,.
d_ ucan be formed by the oxidation of 3-methylbutan-1-ol.

25 the diagram shows the infrared spectrum of an organic compound.
100
transmittance
'% 50
0
4000 3000 2000 1500 1000 500
wavenumber/cm-'
what could be the identity of this compound?
a _propan-1-ol
b _propanal
c_propanoic acid
d_propanone

26 which reagent reacts with both of the —-oh groups in lactic acid, ch3ch(oh)co2h?
a acidified potassium dichromate(vi)
b_ ethanol
c_ sodium
d sodium hydroxide

27 1,2-dibromopropane can be made from 1-bromopropane in two steps.
which row is correct?
[| sept [see
a addition substitution
b elimination addition
cc hydrolysis elimination
d substitution hydrolysis

28 2-methylbut-2-ene reacts with hbr(g) to form two isomeric products. during the reaction two
positively charged intermediates can be made.
which diagram shows the more stable of the two positively charged intermediates?
a b c d
br b
® "©
o = e +o

29 the ester ethyl methanoate is prepared in a school laboratory by reacting a carboxylic acid with
an alcohol.
during the reaction, only 50.0% of the alcohol is converted into the ester.
which mass of alcohol is needed to prepare 10.0g of the ester?
a 3.11g b 8.65g c 12.4g d 32.2g

30 compound x has the structure shown.
compound x
an
which type of carbonyl group is present and how many chiral centres are there in one molecule
of x?
carbonyl chiral
group centres
a aldehyde 0
b aldehyde 1
cc ketone 0
d ketone 1

31. which contain one mole of the underlined substance under room conditions?
1 aballoon containing 24.0 dm? of helium
2 a block of calcium carbonate weighing 100.1 g
3 4000cm? of a 0.250 moldm” solution of sulfuric acid

32 buckminsterfullerene is a fullerene allotrope of carbon.
which statements about buckminsterfullerene are correct?
1 buckminsterfullerene is a giant covalent molecule.
2  buckminsterfullerene has delocalised electrons.
3 buckminsterfullerene has strong intramolecular bonds.

33 gaseous sodium ions can be formed from sodium atoms.
na(s) > na*(g)
which quantities are required to calculate the enthalpy change of formation of na*(g)?
1 first ionisation energy of sodium
2 enthalpy change of atomisation of sodium
3. enthalpy change of formation of sodium

34 the haber process is used in industry to form ammonia from hydrogen and nitrogen.
3h. + no = 2nh3

which statements about the activation energy for this process are correct?

1. the activation energy for the forward reaction is the same as the activation energy for the
reverse reaction.

2 ~the activation energy for the reverse reaction is decreased by the addition of iron.

3 the activation energy is the minimum energy that colliding particles must possess in order to
react.

35 strontium nitrate is heated strongly for several minutes.
which statements are correct?
1 a brown gas is produced.
2 a gas is produced that relights a glowing splint.
3. awhite powder remains after heating.

36 when added to water, which oxides will not cause a change in ph?
1 al203
2 sio,
3 pyoq19

37 propanal reacts with hydrogen cyanide to form 2-hydroxybutanenitrile. a suitable catalyst for this
reaction is sodium cyanide.
nacn
ch3ch,cho + hcn ———® ch3ch2ch(oh)cn
which statements about this catalysed reaction of propanal with hydrogen cyanide are correct?
1 the sodium cyanide provides a stronger nucleophile than hcn.
2 the reaction can be classified as nucleophilic substitution.
3 the hydrogen cyanide molecule attacks the propanal molecule to form an intermediate ion.

38 a reaction mechanism is shown.
ao. a aa
“\ /- “\ i. * of
an 2 am ie
ho 4 ah
which statements about this reaction are correct?
1 it is a substitution reaction.
2 oh behaves as a nucleophile.
3. _heterolytic bond fission is involved.

39 oncomplete combustion, a sample of x produces 44g of carbon dioxide and 27 g of water.
on complete combustion, a sample of y produces 44g of carbon dioxide and 18g of water.
on complete combustion, a sample of z produces 22g of carbon dioxide and 9g of water.
which substances could be straight chain alkanes?
1 xx
2 sy
3. z

40 which pairs are structural isomers of each other?
1. ch3ch2ch2ch2ch2co2h and ch3ch2zch2co2ch2ch3
2 ay and “~~
3. =chsch2zch2zch(oh)ch2ch3 and ch3ch2ch(oh)ch2ch2ch3

Solve 9701_s20_qp_13