Download T10 SL - MsReenChemistry

1.
Which of the following statements about alkenes is not correct?
A.
They have reactive double bonds.
B.
They can form addition polymers.
C.
They react mainly by substitution.
D.
They can react with water to form alcohols.
(Total 1 mark)
2.
What is the type of mechanism and an important feature of the reaction between C(CH3)3Br and
aqueous NaOH?
Mechanism
Feature
A.
SN1
a transition state
B.
SN1
an intermediate
C.
SN2
a transition state
D.
SN2
an intermediate
(Total 1 mark)
3.
Which of the following are isomers of pentane?
I.
2-methylpentane
II.
methylbutane
III.
dimethylpropane
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
IB Questionbank Chemistry
1
4.
Which of the following pairs are members of the same homologous series?
A.
CH3CH2CH2OH and CH3CH2CHO
B.
CH3CH(OH)CH3 and CH3CH2CH(OH)CH3
C.
CH3COCH3 and CH3CH2COOH
D.
CH3COCH2CH3 and CH3CH2CHO
(Total 1 mark)
5.
Alkenes are important starting materials for a variety of products.
(a)
State and explain the trend of the boiling points of the first five members of the alkene
homologous series.
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(3)
(b)
Describe two features of a homologous series.
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(2)
(Total 5 marks)
IB Questionbank Chemistry
2
6.
Below is a schematic diagram representing some reactions of ethene. The letters A–D represent
the organic compounds formed from the reactants and catalysts shown.
Deduce the structural formulas of compounds A, B, C, and D and state the IUPAC name of
compound C.
IB Questionbank Chemistry
3
A:
B:
C:
IUPAC name: ..............................................................................................................
D:
(Total 5 marks)
7.
Describe a chemical test that could be used to distinguish between pent-1-ene and pentane.
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(Total 2 marks)
IB Questionbank Chemistry
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8.
State and explain whether the following molecules are primary, secondary or tertiary
halogenoalkanes.
E:
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F:
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G:
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(Total 4 marks)
IB Questionbank Chemistry
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9.
Explain, using equations, the following steps in the free-radical mechanism of the reaction of
methane with chlorine.
•
•
•
Initiation
Propagation
Termination
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(Total 4 marks)
IB Questionbank Chemistry
6
10.
Two compounds, A and D, each have the formula C4H9Cl.
Compound A is reacted with dilute aqueous sodium hydroxide to produce compound B with a
formula of C4H10O. Compound B is then oxidized with acidified potassium manganate(VII) to
produce compound C with a formula of C4H8O. Compound C resists further oxidation by
acidified potassium manganate(VII).
Compound D is reacted with dilute aqueous sodium hydroxide to produce compound E with a
formula of C4H10O. Compound E does not react with acidified potassium manganate(VII).
Deduce the structural formulas for compounds A, B, C, D and E.
A:
B:
C:
D:
E:
(Total 5 marks)
IB Questionbank Chemistry
7
11.
2-chloro-3-methylbutane reacts with sodium hydroxide via an SN2 mechanism.
Explain the mechanism by using curly arrows to represent the movement of electron pairs.
(Total 4 marks)
12.
Which organic molecule is not a structural isomer of pentan-1-ol?
A.
pentan-2-ol
B.
2-methylpentan-2-ol
C.
2-methylbutan-2-ol
D.
pentan-3-ol
(Total 1 mark)
13.
Which of the structures below is an aldehyde?
A.
CH3CH2CH2CH2OH
B.
CH3CH2COCH3
C.
CH3CH2COOCH3
D.
CH3CH2CH2CHO
(Total 1 mark)
IB Questionbank Chemistry
8
14.
What product is formed when CH3CH(OH)CH3 is reacted with acidified potassium
dichromate(VI)?
A.
CH3COOCH3
B.
CH3CH2CHO
C.
CH3CH2COOH
D.
CH3COCH3
(Total 1 mark)
15.
Which type of reaction occurs when 2-iodo-2-methylpropane, C(CH3)3I, reacts with aqueous
sodium hydroxide, NaOH(aq)?
A.
Addition
B.
Free-radical substitution
C.
SN1
D.
SN2
(Total 1 mark)
16.
(i)
Describe a chemical test that could be used to distinguish between propane and propene.
In each case state the result of the test.
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(2)
IB Questionbank Chemistry
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(ii)
Under certain conditions propene can polymerize to form poly(propene). State the type of
polymerization taking place and draw a section of the polymer to represent the repeating
unit.
......................................................................................................................................
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(2)
(iii)
Other than polymerization, state one reaction of alkenes which is of economic
importance.
......................................................................................................................................
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(1)
(Total 5 marks)
17.
Propan-1-ol and propan-2-ol are two structural isomers of C3H8O.
(i)
State the equation for the complete combustion of C3H8O.
......................................................................................................................................
......................................................................................................................................
(2)
(ii)
Both propan-1-ol and propan-2-ol can be oxidized in aqueous solution by potassium
dichromate(VI). State any necessary conditions for the oxidation to occur and describe
the colour change during the oxidation process.
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(3)
IB Questionbank Chemistry
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(iii)
State the name(s) and structure(s) of the organic product(s) that can be formed when each
of the alcohols is oxidized and suggest why one of the alcohols gives two organic
products and the other only gives one organic product.
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(5)
(Total 10 marks)
18.
Halogenoalkanes can undergo SN1 and SN2 reactions with aqueous sodium hydroxide.
Which halogenoalkane will react fastest with a 0.1 mol dm–3 solution of aqueous sodium
hydroxide?
A.
2-chloro-2-methylpropane
B.
2-iodo-2-methylpropane
C.
1-chlorobutane
D.
1-iodobutane
(Total 1 mark)
IB Questionbank Chemistry
11
19.
There are several structural isomers with the molecular formula C5H11Br.
(a)
Deduce the name of one of the isomers which can exist as enantiomers and draw
three-dimensional representations of its two enantiomers.
......................................................................................................................................
(3)
(b)
All the isomers react when warmed with a dilute aqueous solution of sodium hydroxide
according to the equation below.
C5H11Br + NaOH → C5H11OH + NaBr
(i)
The reaction with 1-bromopentane proceeds by an SN2 mechanism. Describe this
mechanism using structural formulas and curly arrows to represent the movement
of electron pairs.
(3)
IB Questionbank Chemistry
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(ii)
The reaction with 2-bromo-2-methylbutane proceeds by an SN1 mechanism.
Describe this mechanism using structural formulas and curly arrows to represent
the movement of electron pairs.
(3)
(iii)
Explain why 1-bromopentane reacts by an SN2 mechanism whereas
2-bromo-2-methylbutane reacts by an SN1 mechanism.
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(3)
(iv)
Explain whether the boiling point of 1-bromopentane will be higher, lower or the
same as that of 2-bromo-2-methylbutane.
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(3)
IB Questionbank Chemistry
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(v)
The product C5H11OH formed from the reaction with 1-bromopentane is warmed
with ethanoic acid in the presence of a few drops of concentrated sulfuric acid.
State the name of the type of reaction taking place and the structural formula of the
organic product.
...........................................................................................................................
...........................................................................................................................
(2)
(c)
If the conditions of the reaction in (b) are changed so that a hot solution of sodium
hydroxide in ethanol is used then a different reaction occurs. The reaction with
2-bromo-2-methylbutane gives two different organic products. State the type of reaction
taking place and suggest the identity (name or structure) of these two products.
Explain whether or not they can exist as geometrical isomers.
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(4)
(Total 21 marks)
20.
Which is the best definition of structural isomers?
A.
Compounds which have atoms with the same atomic numbers but different mass numbers
B.
Compounds which have the same general formula but differ by a CH2 group
C.
Compounds which have the same empirical formula but different molecular formulas
D.
Compounds which have the same molecular formula but different arrangements of atoms
(Total 1 mark)
IB Questionbank Chemistry
14
21.
Which is the correct classification of these alcohols?
1
2
1
2
3
3
A.
tertiary
secondary
primary
B.
tertiary
primary
secondary
C.
tertiary
tertiary
secondary
D.
secondary
primary
secondary
(Total 1 mark)
22.
Which substances are possible products of the incomplete combustion of octane?
A.
Carbon dioxide and hydrogen gas
B.
Carbon monoxide and water vapour
C.
Carbon monoxide and hydrogen gas
D.
Methane and hydrogen gas
(Total 1 mark)
IB Questionbank Chemistry
15
23.
Which structure could represent a repeating unit of a polymer formed from propene?
A.
( CH2–CH(CH3) )
B.
( CH2–CH2–CH2 )
C.
( CH(CH3)–CH(CH3) )
D.
( CH2–CH2 )
(Total 1 mark)
24.
Chloroethene, C2H3Cl, is an important organic compound used to manufacture the polymer
poly(chloroethene).
(i)
Draw the Lewis structure for chloroethene and predict the H – C– Cl bond angle.
......................................................................................................................................
(2)
(ii)
Draw a section of poly(chloroethene) containing six carbon atoms.
(1)
IB Questionbank Chemistry
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(iii)
Outline why the polymerization of alkenes is of economic importance and why the
disposal of plastics is a problem.
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(2)
(Total 5 marks)
25.
(i)
Chloroethene can be converted to ethanol in two steps. For each step deduce an overall
equation for the reaction taking place.
Step 1:
......................................................................................................................................
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Step 2:
......................................................................................................................................
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(2)
(ii)
State the reagents and conditions necessary to prepare ethanoic acid from ethanol in the
laboratory.
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(2)
IB Questionbank Chemistry
17
(iii)
State an equation, including state symbols, for the reaction of ethanoic acid with water.
Identify a Brønsted-Lowry acid in the equation and its conjugate base.
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(3)
(Total 7 marks)
26.
Ethanol is part of the homologous series of alcohols. Describe two features of a homologous
series.
(Total 2 marks)
IB Questionbank Chemistry
18
27.
(a)
(i)
Below are four structural isomers of alcohols with molecular formula C4H10O.
State the name of each of the isomers A, B, C and D.
(4)
(ii)
Determine the isomer that cannot be oxidized by acidified potassium
dichromate(VI), K2Cr2O7.
(1)
(iii)
Determine the isomer which can be oxidized to butanal.
(1)
(iv)
Determine the isomer which can be oxidized to butanone.
(1)
(v)
Suggest the structural formula of another isomer of C4H10O.
(1)
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19
(b)
(i)
Isomer A is formed by reacting 1-bromobutane with aqueous sodium hydroxide.
State whether the reaction would proceed via an SN1 or SN2 mechanism.
(1)
(ii)
Explain the mechanism named in part (b) (i) using curly arrows to represent the
movement of electron pairs.
(3)
(Total 12 marks)
28.
Outline the different mechanisms involved in the manufacture of low-density poly(ethene) and
high-density poly(ethene).
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(Total 2 marks)
29.
What is the structural formula of 2,3-dibromo-3-methylhexane?
A.
CH3CHBrCHBrCH(CH3)CH2CH3
B.
CH3CHBrCBr(CH3)CH2CH2CH3
C.
CH3CH2CHBrCBr(CH2CH3)2
D.
CH3CHBrCHBrCH(CH2CH3)2
(Total 1 mark)
IB Questionbank Chemistry
20
30.
What happens when a few drops of bromine water are added to excess hex-1-ene and the
mixture is shaken?
I.
The colour of the bromine water disappears.
II.
The organic product formed does not contain any carbon-carbon double bonds.
III.
2-bromohexane is formed.
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
31.
What is the product of the following reaction?
2

Cr2 O 7 /H
CH3CH(OH)CH3 


A.
CH3COOH
B.
CH3COCH3
C.
CH3CH2COOH
D.
CH3CH2CH3
(Total 1 mark)
IB Questionbank Chemistry
21
(iii)
State an equation, including state symbols, for the reaction of ethanoic acid with water. Identify
a Brønsted-Lowry acid in the equation and its conjugate base.
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(3)
(Total 7 marks)
32.
Alkenes are an economically and chemically important family of organic compounds.
(i)
The reaction of alkenes with bromine water provides a test for unsaturation in the
laboratory. Describe the colour change when bromine water is added to chloroethene.
(1)
(ii)
Deduce the Lewis structure of chloroethene and identify the formula of the repeating unit
of the polymer poly(chloroethene).
(2)
(iii)
Besides polymerization, state two commercial uses of the reactions of alkenes.
(2)
(Total 5 marks)
IB Questionbank Chemistry
22
A.
CH3COOH
B.
CH3COCH3
C.
CH3CH2COOH
D.
CH3CH2CH3
(Total 1 mark)
tx1ÈŽ?ÈŽ?(iii)
State an equation, including state symbols, for the reaction of ethanoic acid with
water. Identify a Brønsted-Lowry acid in the equation and its conjugate base.
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(3)
(Total 7 marks)
33.
But-2-ene can be converted to butan-2-one in two stages.
(i)
Draw the structural formulas of but-2-ene and butan-2-one.
(2)
(ii)
Deduce a reaction pathway for the two stages of the reaction. Your answer should include
the fully balanced equation for each stage of the reaction and the reagents and conditions
for the two stages.
(5)
(Total 7 marks)
IB Questionbank Chemistry
23
(2)
(Total 5 marks)
00äú?äú?
22253797374656d0093a515669300000a0021008a01000000000000000028fc1300040000002d0100
0004000000f0010100030000000000
A.
CH3COOH
B.
CH3COCH3
C.
CH3CH2COOH
D.
CH3CH2CH3
(Total 1 mark)
tx1ÈŽ?ÈŽ?(iii)
State an equation, including state symbols, for the reaction of ethanoic acid with
water. Identify a Brønsted-Lowry acid in the equation and its conjugate base.
......................................................................................................................................
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......................................................................................................................................
(3)
(Total 7 marks)
34.
(i)
Deduce the structural formulas of the two alcohol isomers of molecular formula C3H8O.
Name each isomer and identify each as either a primary or a secondary alcohol.
(3)
IB Questionbank Chemistry
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(ii)
Oxidation of the alcohol isomers lead to the formation of different organic products.
Determine the structures of the organic products formed from the oxidation of each
alcohol isomer in (i) above and list the conditions required to obtain the different
products.
(5)
(Total 8 marks)
aiHÓß HÓß mmercial uses of the reactions of alkenes.
(2)
(Total 5 marks)
00äú?äú?
22253797374656d0093a515669300000a0021008a01000000000000000028fc1300040000002d0100
0004000000f0010100030000000000
A.
CH3COOH
B.
CH3COCH3
C.
CH3CH2COOH
D.
CH3CH2CH3
(Total 1 mark)
IB Questionbank Chemistry
25
tx1ÈŽ?ÈŽ?(iii)
State an equation, including state symbols, for the reaction of ethanoic acid with
water. Identify a Brønsted-Lowry acid in the equation and its conjugate base.
......................................................................................................................................
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(3)
(Total 7 marks)
35.
What organic product is formed in the following reaction?
H 2SO 4


(CH3CH2)CH=CH(CH2CH3) + H2O 
A.
CH3(CH2)2CH(OH)CH2CH3
B.
CH3(CH2)5CH3
C.
CH3(CH2)2CH(OSO3H)CH2CH3
D.
CH3(CH2)6OH
(Total 1 mark)
IB Questionbank Chemistry
26
36.
Which of the following substances are structural isomers of each other?
I.
CH3(CH2)3CH3
II.
(CH3)2CHCH3
III.
CH3CH(CH3)CH2CH3
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
37.
Which order is correct when the following substances are arranged in order of increasing
boiling point?
A.
CH3CH3 < CH3CHO < CH3CH2OH
B.
CH3CHO < CH3CH2OH < CH3CH3
C.
CH3CH2OH < CH3CH3 < CH3CHO
D.
CH3CH3 < CH3CH2OH < CH3CHO
(Total 1 mark)
IB Questionbank Chemistry
27
38.
Which monomer could be used to form a polymer with the following repeating unit?
A.
CH3CH2Cl
B.
CH2ClCH2Cl
C.
CH2CHCl
D.
CHClCHCl
(Total 1 mark)
39.
Which reaction pathway describes how ethanol can be formed?
A.
addition
elimination

 chloroethane 
  ethanol
ethene 
B.
substitution
nucleophilic substitution

 chloroethane 

 ethanol
ethane 
C.
substitution

 ethanol
ethene 
D.
addition

 ethanol
ethane 
(Total 1 mark)
IB Questionbank Chemistry
28
40.
The alkenes are an example of a homologous series.
(a)
State the name of the alkene shown.
......................................................................................................................................
(1)
(b)
Bromine water, Br2(aq), can be used to distinguish between the alkanes and the alkenes.
(i)
Describe the colour change observed when the alkene shown in part (a) is added to
bromine water.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Draw the structural formula and state the name of the product formed.
...........................................................................................................................
(2)
(Total 4 marks)
IB Questionbank Chemistry
29
41.
The polymerization of the alkenes is one of the most significant reactions of the twentieth
century.
(i)
Outline two reasons why the polymers of the alkenes are of economic importance.
......................................................................................................................................
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......................................................................................................................................
......................................................................................................................................
(2)
(ii)
State the type of polymerization reaction shown by the alkene below.
......................................................................................................................................
......................................................................................................................................
(1)
(iii)
Deduce the structure of the resulting polymer showing three repeating units.
(1)
IB Questionbank Chemistry
30
(iv)
Explain why monomers are often gases or volatile liquids, but polymers are solids.
......................................................................................................................................
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......................................................................................................................................
......................................................................................................................................
(2)
(Total 6 marks)
42.
State the name of the product and identify the type of reaction which occurs between ethene and
hydrogen chloride.
(Total 2 marks)
43.
Consider the following sequence of reactions.
reaction1
reaction 2
reaction3
 RCH2Br 
 RCH2OH 
 RCOOH
RCH3 
RCH3 is an unknown alkane in which R represents an alkyl group.
(a)
The alkane contains 81.7 % by mass of carbon. Determine its empirical formula, showing
your working.
(3)
(b)
Equal volumes of carbon dioxide and the unknown alkane are found to have the same
mass, measured to an accuracy of two significant figures, at the same temperature and
pressure. Deduce the molecular formula of the alkane.
(1)
(c)
(i)
State the reagent and conditions needed for reaction 1.
(2)
(ii)
State the reagent(s) and conditions needed for reaction 3.
(2)
IB Questionbank Chemistry
31
(d)
Reaction 1 involves a free-radical mechanism. Describe the stepwise mechanism, by
giving equations to represent the initiation, propagation and termination steps.
(4)
(e)
The mechanism in reaction 2 is described as SN2.
(i)
State the meaning of each of the symbols in SN2.
(1)
(ii)
Explain the mechanism of this reaction using curly arrows to show the movement
of electron pairs, and draw the structure of the transition state.
(3)
(Total 16 marks)
44.
Propan-1-ol has two structural isomers.
(i)
Deduce the structural formula of each isomer.
(2)
(ii)
Identify the isomer from part (i) which has the higher boiling point and explain your
choice. Refer to both isomers in your explanation.
(2)
(Total 4 marks)
45.
Which three compounds can be considered to be a homologous series?
A.
CH3OH,
CH3CH2OH,
B.
CH3CH2OH,
C.
CH3CH2CH(OH)CH3,
D.
CH3CH2CH2CH2OH,
CH3CH2CH2OH
CH3CHO,
CH3COOH
CH3CH2CH2CH2OH,
CH3CH2OCH2CH3,
(CH3)3COH
(CH3)2CH2CHO
(Total 1 mark)
IB Questionbank Chemistry
32
46.
What is the IUPAC name for CH3CH2CH(CH3)CH3?
A.
1,1-dimethylpropane
B.
2-ethylpropane
C.
2-methylbutane
D.
3-methylbutane
(Total 1 mark)
3CH2CH2CH2OH,
D.
(CH3)3COH
CH3CH2CH2CH2OH,
CH3CH2OCH2CH3,
(CH3)2CH2CHO
(Total 1 mark)
47.
When bromine water is shaken with a liquid organic compound, it is rapidly decolorized. What
can be determined from this test?
A.
The compound is an alcohol.
B.
The compound is an alkane.
C.
The compound is an alkene.
D.
The compound is an iodoalkane.
(Total 1 mark)
IB Questionbank Chemistry
33
48.
Which conditions are required to obtain a good yield of a carboxylic acid when ethanol is
oxidized using potassium dichromate(VI), K2Cr2O7(aq)?
I.
Add sulfuric acid
II.
Heat the reaction mixture under reflux
III.
Distil the product as the oxidizing agent is added
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
2OH,
CH3CH2OCH2CH3,
(CH3)2CH2CHO
(Total 1 mark)
49.
Three compounds with similar relative molecular masses are butane, propanal and propan-1-ol.
(i)
List the three compounds in order of increasing boiling point (lowest first) and explain
the differences in their boiling points.
(4)
(ii)
Predict, with an explanation, which of the three compounds is least soluble or miscible in
water.
(2)
(iii)
When propan-1-ol is oxidized using a warm acidified solution of potassium
dichromate(VI) two different organic products can be obtained. Deduce the name and
structural formula for each of these two products.
(3)
(iv)
Propan-2-ol is an isomer of propan-1-ol. Draw the structure of propan-2-ol.
(1)
IB Questionbank Chemistry
34
(v)
Identify the class of alcohols that propan-2-ol belongs to and state the name of the organic
product formed when it is oxidized by an acidified solution of potassium dichromate(VI).
(2)
(Total 12 marks)
50.
Ethanol can be formed from ethene in a two step reaction:
(i)
State the name of the reagent used for step 1.
(1)
(ii)
State the name of the reagent and the conditions used for step 2.
(2)
(iii)
The mechanism involved in step 2 is SN2. Explain how the reaction proceeds using curly
arrows to represent the movement of electron pairs.
(3)
(iv)
Outline how ethanol is manufactured from ethene in industry and state one important
commercial use of ethanol.
(2)
(Total 8 marks)
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51.
What is the product of the oxidation of butan-2-ol?
A.
But-2-ene
B.
Butanoic acid
C.
Butanal
D.
Butanone
(Total 1 mark)
52.
Which is a tertiary halogenoalkane?
A.
CH3CH2CH2Br
B.
CH3CH2CH(CH3)Cl
C.
C(CH3)3Br
D.
CH3CHClCH2CH3
(Total 1 mark)
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53.
What is the IUPAC name of the following compound?
A.
2-methylbutane
B.
Ethylpropane
C.
3-methylbutane
D.
Pentane
(Total 1 mark)
54.
Which equations represent the incomplete combustion of methane?
I.
CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
II.
CH4(g) + 1½O2(g) → CO(g) + 2H2O(g)
III.
CH4(g) + O2(g) → C(s) + 2H2O(g)
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
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55.
In some countries, ethanol is mixed with gasoline (petrol) to produce a fuel for cars called
gasohol.
(i)
Define the term average bond enthalpy.
(2)
(ii)
Use the information from Table 10 of the Data Booklet to determine the standard
enthalpy change for the complete combustion of ethanol.
CH3CH2OH(g) + 3O2(g) → 2CO2(g) + 3H2O(g)
(3)
(iii)
The standard enthalpy change for the complete combustion of octane, C8H18, is
–5471 kJ mol–1. Calculate the amount of energy produced in kJ when 1 g of ethanol and
1 g of octane is burned completely in air.
(2)
(iv)
Ethanol can be oxidized using acidified potassium dichromate, K2Cr2O7, to form two
different organic products.
CH3CH2OH
A
B
State the structural formulas of the organic products A and B and describe the conditions
required to obtain a high yield of each of them.
(4)
(v)
Deduce and explain whether ethanol or A has the higher boiling point.
(2)
(vi)
Ethene can be converted into ethanol by direct hydration in the presence of a catalyst
according to the following equation.
C2H4(g) + H2O(g)
CH3CH2OH(g)
For this reaction identify the catalyst used and state one use of the ethanol formed other
than as a fuel.
(2)
(Total 15 marks)
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56.
(i)
State the name of one structural isomer of pentane.
(1)
(ii)
Sodium hydroxide reacts with 1-bromopentane via an SN2 mechanism.
Describe the mechanism of this reaction using curly arrows to represent the movement of
electron pairs.
(4)
(Total 5 marks)
57.
What structural feature must a molecule have in order to undergo addition polymerization?
A.
Two functional groups
B.
A carbon–carbon double bond
C.
Carbon atoms singly bonded together
D.
A polar covalent bond
(Total 1 mark)
58.
Ethanol can be oxidized using acidified potassium dichromate, K2Cr2O7, to form two different
organic products.
CH3CH2OH
A
B
State the structural formulas of the organic products A and B and describe the conditions
required to obtain a high yield of each of them.
(Total 4 marks)
59.
Ethene can be converted into ethanol by direct hydration in the presence of a catalyst according
to the following equation.
C2H4(g) + H2O(g)
CH3CH2OH(g)
For this reaction, identify the catalyst used and state one use of the ethanol formed other than as
a fuel.
(Total 2 marks)
IB Questionbank Chemistry
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60.
How many structural isomers exist with the formula C3H5Cl3?
A.
3
B.
4
C.
5
D.
6
(Total 1 mark)
61.
Which substance is produced by the reaction of hydrogen with a vegetable oil?
A.
Margarine
B.
Nylon
C.
Polypropene
D.
Soap
(Total 1 mark)
62.
Which substance is not produced during the combustion of alkanes?
A.
CO2
B.
CO
C.
C
D.
H2
(Total 1 mark)
IB Questionbank Chemistry
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63.
Propene is converted to propanone in a two stage process.
Propene → X → Propanone
What is the formula of compound X?
A.
CH3CHBrCH3
B.
CH3CH2CH2Br
C.
CH3CHOHCH3
D.
CH3CH2CH2OH
(Total 1 mark)
64.
(a)
The boiling points of the isomers of pentane, C5H12, shown are 10, 28 and 36 °C, but not
necessarily in that order.
(i)
Identify the boiling points for each of the isomers A, B and C and state a reason for
your answer.
Isomer
A
B
C
Boiling point
...........................................................................................................................
...........................................................................................................................
(3)
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(ii)
State the IUPAC names of isomers B and C.
B: .......................................................................................................................
C: .......................................................................................................................
(2)
(b)
Both C5H12 and C5H11OH can be used as fuels. Predict which compound would release a
greater amount of heat per gram when it undergoes complete combustion. Suggest two
reasons to support your prediction.
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
(3)
(Total 8 marks)
65.
Halogenoalkanes can undergo substitution reactions with potassium hydroxide solution.
(i)
State an equation for the reaction of C4H9Cl with KOH.
(1)
(ii)
Substitution reactions may occur by either of two mechanisms namely SN1 or SN2.
Outline the meaning of the term SN1.
(2)
(iii)
Predict the mechanism (SN1 or SN2) expected for the reaction of the following
halogenoalkanes with aqueous KOH.
1-chlorobutane to form butan-1-ol
2-chloro-2-methylpropane to form 2 methylpropan-2-ol.
(2)
IB Questionbank Chemistry
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(iv)
Explain the mechanism of each reaction in part (iii) using curly arrows to represent the
movement of electron pairs.
(6)
(Total 11 marks)
66.
(i)
Draw four structural isomers of molecular formula C4H10O which contain the –OH
group.
(4)
(ii)
On reaction with acidified potassium dichromate(VII), two of the isomers are oxidized in
two steps to produce different products. Draw the structural formula of the two products
formed from one of the isomers.
(2)
(iii)
A third isomer is oxidized in one step. Draw the structural formula of the organic product
formed.
(1)
(iv)
State the colour change that takes place in these oxidation reactions.
(1)
(v)
Identify the isomer which resists oxidation by acidified potassium dichromate(VI).
(1)
(Total 9 marks)
67.
Which statement about successive members of all homologous series is correct?
A.
They have the same empirical formula.
B.
They differ by a CH2 group.
C.
They have the same physical properties.
D.
They differ in their degree of unsaturation.
(Total 1 mark)
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68.
The following is a three-dimensional representation of an organic molecule.
Which statement is correct?
A.
The correct IUPAC name of the molecule is 2-methylpentane.
B.
All the bond angles will be approximately 90°.
C.
One isomer of this molecule is pentane.
D.
The boiling point of this compound would be higher than that of pentane.
(Total 1 mark)
IB Questionbank Chemistry
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69.
Which compound forms when hydrogen bromide is added to but-2-ene?
A.
2-bromobutane
B.
2,3-dibromobutane
C.
1-bromobutane
D.
1,2-dibromobutane
(Total 1 mark)
70.
Which products can be potentially obtained from crude oil and are economically important?
I.
II.
III.
Plastics
Margarine
Motor fuel
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
(Total 1 mark)
71.
Propane, C3H8, undergoes incomplete combustion in a limited amount of air. Which products
are most likely to be formed during this reaction?
A.
Carbon monoxide and water
B.
Carbon monoxide and hydrogen
C.
Carbon dioxide and hydrogen
D.
Carbon dioxide and water
(Total 1 mark)
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72.
(a)
List two characteristics of a homologous series.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(b)
Ethanol and ethanoic acid can be distinguished by their melting points. State and explain
which of the two compounds will have a higher melting point.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(c)
Draw the three isomers containing the alcohol functional group of formula C4H9OH.
(2)
(Total 5 marks)
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73.
The following is a computer-generated representation of the molecule, methyl
2-hydroxy benzoate, better known as oil of wintergreen.
(i)
Deduce the empirical formula of methyl 2-hydroxy benzoate and draw the full structural
formula, including any multiple bonds that may be present.
The computer-generated representation shown does not distinguish between single and
multiple bonds.
(2)
(ii)
In this representation, two of the carbon-oxygen bond lengths shown are 0.1424 nm and
0.1373 nm. Explain why these are different and predict the carbon-oxygen bond length in
carbon dioxide.
(2)
(iii)
Name all the functional groups present in the molecule.
(2)
(Total 6 marks)
IB Questionbank Chemistry
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74.
(i)
State and explain the trend in the boiling points of the first six alkanes involving
straight-chains.
(2)
(ii)
Write an equation for the reaction between methane and chlorine to form chloromethane.
Explain this reaction in terms of a free-radical mechanism.
(5)
(Total 7 marks)
75.
(i)
Identify the formulas of the organic products, A–E, formed in the reactions, I–IV:


I.
H
H
CH3(CH2)8OH + K2Cr2O7 
 A 
 B
II.
(CH3)3CBr + NaOH  C
III.
H
(CH3)2CHOH + K2Cr2O7 
 D
IV.
 E
H2C=CH2 + Br2 

(5)
(ii)
H2C=CH2 can react to form a polymer. Name this type of polymer and draw the
structural formula of a section of this polymer consisting of three repeating units.
(2)
(Total 7 marks)
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