IGCSE Chemistry Multiple Choice Questions: Chapter 18
Chapter 18 Introducing Organic Chemistry
18.1
Which one of the following molecules is butane?
A
CH3CH2CH3
B
CH3CH2CH2CH3
C
CH3CH2CH=CH2
D
CH3CH2CH2CH2CH3
18.2
Which one of the following molecules is propene?
A
CH3CH=CH2
B
CH3CH2CH3
C
CH3CH2CH=CH2
D
CH3CH2CH2CH3
18.3
What is the name of this hydrocarbon?
A
pentane
B
2-methylpropane
C
3-methylbutane
D
2-methylbutane
IGCSE Chemistry Multiple Choice Questions: Chapter 18
18.4
What is the name of the molecule CH3CH2CH2OH ?
A
propane
B
ethanol
C
propan-1-ol
D
propan-2-ol
18.5
CH3

What is the name of the molecule CH3CHCHCH3 ?

CH3
A
hexane
B
2,3-dimethylpropane
C
2,3-dimethylbutane
D
2,3-dimethylpentane
18.5*
This question is about 2,2,3-trimethylpentan-3-ol. The name gives you several bits of
information about the structure of the molecule. Which one of the following bits of
information is wrong?
A
The longest chain of carbon atoms in the molecule is 5 carbon atoms long.
B
There is an -OH group attached to the third carbon atom in the chain.
C
The chain contains a carbon–carbon double bond between the second and
third carbon atom.
D
There are three methyl groups attached to the chain – two attached to the
second carbon, and one attached to the third.
IGCSE Chemistry Multiple Choice Questions: Chapter 18
18.6
How many isomers are there for the molecular formula C4H10?
A
1
B
2
C
3
D
4
18.7
Structural isomers are molecules with the same molecular formula, but with different
structural formulae. A student was asked to draw all the isomers for pentane, C5H12,
and came up with the following four structures.
(i)
CH3  CH2  CH2  CH2  CH3
(ii)
CH3

CH3  CH2  CH  CH3
(iii)
(iv)
CH3

CH3  C  CH3

CH3
CH3  CH  CH3

CH2

CH3
Unfortunately, in reality there are only three isomers of pentane. Two of the
structures drawn represent the same molecule. Which two?
A
(i) and (ii)
B
(i) and (iv)
C
(ii) and (iii)
D
(ii) and (iv)
IGCSE Chemistry Multiple Choice Questions: Chapter 18
18.7*
Which one of the following is not an isomer of C3H8O ?
A
CH3  CH2  CH2  OH
B
CH3  CH2  O  CH3
C
CH3  CH  CH3

OH
D
CH2  CH2


CH2  O
18.8
But-2-ene, CH3CH=CHCH3 , is one of the structural isomers of C4H8. How many other
structural isomers of this are there (in addition to this one) which contain a C=C
double bond?
A
1
B
2
C
3
D
IGCSE Chemistry Multiple Choice Questions: Chapter 19
Chapter 19
Alkanes, Alkenes and Alcohols
19.1
Which one of the following statements about the alkanes is wrong?
A
They are a family of hydrocarbons.
B
They all have similar physical properties.
C
They are saturated.
D
Many of them are useful fuels.
19.1*
The formula for the alkane with 17 carbon atoms is
A
C17H32
B
C17H34
C
C17H36
D
C17H38
19.2
The correct equation for the complete combustion of octane, C8H18, is
A
2C8H18(l) + 25O2(g)  16CO2(g) + 18H2O(l)
B
C8H18(l) + 12O2(g)  8CO2(g) + 9H2O(l)
C
2C8H18(l) + 17O2(g)  16CO(g) + 18H2O(l)
D
C8H18(l) + 9O2(g)  8CO(g) + 9H2O(l)
IGCSE Chemistry Multiple Choice Questions: Chapter 19
19.3
Which one of the following statements about the reaction between methane and
bromine is wrong?
A
It is a substitution reaction.
B
It needs the presence of ultra-violet light (for example, sunlight) to work at a
reasonable rate.
C
Bromoethane and hydrogen bromide are formed.
D
A brown mixture of bromine and methane gases loses its colour.
19.4
Which one of the following statements about alkenes is wrong?
A
Alkenes are unsaturated hydrocarbons.
B
Alkenes contain a C=C double bond.
C
Alkenes undergo addition reactions.
D
The reaction between ethene and bromine produces CH3CH2Br.
19.5
A liquid organic compound was shaken with bromine water, and the brown bromine
water became colourless.
Which one of the following could the organic compound be?
A
propene
B
hex-1-ene
C
hexane
D
ethanol
IGCSE Chemistry Multiple Choice Questions: Chapter 19
19.6
Ethanol can be manufactured by the reaction between ethene and steam. The key
reaction is
CH2=CH2(g) + H2O(g)  CH3CH2OH(g)
Which one of the following is the correct set of conditions for the reaction?
A
temp: 300°C;
press: 60-70 atm;
catalyst: phosphoric acid
B
temp: 60-70°C;
press: 300 atm;
catalyst: phosphoric acid
C
temp: 60-70°C;
press: 300 atm;
catalyst: vanadium(V) oxide
D
temp: 300°C;
press: 60-70 atm;
catalyst: iron
19.7
Which one of the following statements does not describe an advantage that making
ethanol by the direct hydration of ethene has over making it by fermentation?
A
Making ethanol by direct hydration of ethene is a continuous flow process.
B
Making ethanol by direct hydration of ethene produces purer alcohol.
C
Making ethanol by direct hydration of ethene is faster.
D
Making ethanol by direct hydration uses higher temperatures and pressures.
19.7*
Alcohols can be dehydrated by passing their vapour over a hot aluminium oxide
catalyst. If propan-1-ol, CH3CH2CH2OH, vapour is passed over hot aluminium oxide,
which one of the following organic compounds would be formed?
A
CH3CH=CH2
B
CH3CH2CH3
C
CH2=CH2
D
CH3CH3
IGCSE Chemistry Multiple Choice Questions: Chapter 19
19.8
Hexan-1-ol is an alcohol with a six carbon chain. All of the following statements about
hexan-1-ol are true except one. Which one is false?
A
Hexan-1-ol burns to form carbon dioxide and water.
B
Hexan-1-ol dehydrates to form hex-1-ene when its vapour is passed over hot
aluminium oxide.
C
The intermolecular forces between hexan-1-ol molecules are weaker than
those between ethanol molecules.
D
Hexan-1-ol boils at 157°C.