DIOCESAN COLLEGE - BISHOPS
Grade 12 HG
Physical Science – Class Test – Organic Chemistry
18 August 2005
Total : 72 marks
Time : 40 minutes
QUESTION 1 : Multiple Choice Questions – Write down the letter corresponding to the correct answer.
1.1
If the molecular formula of an ester is C2H4O2 the IUPAC name of the ester is
A
B
C
D
1.2
Bromine water loses its colour when propene gas is bubbled through it. Which one of the
following compounds is the product of this reaction?
A
B
C
D
1.3
ethyl ethanoate
methyl ethanoate
ethyl methanoate
methyl methanoate
1,2 - dibromopropene
1,1 - dibromopropane
1,2 - dibromopropane
1,1,2,2 - tetrabromopropane
What is the correct IUPAC name for the following organic compound?
CH3
CH
C
CH3
CH3
A
B
C
D
1.4
Which one of the following compounds will de-colourise bromine water most rapidly?
A
C
1.5
3,3 dimethyl pentene
2 methyl but-2-ene
3 methyl but-2-ene
2 methyl pent-2-ene
C2H6
C3H6
B
D
C2H5OH
C4H10
From which TWO substances can ethyl methanoate be prepared?
A
B
C
D
methanoic acid and ethanol
ethanol and water
methanol and ethanoic acid
ethylene methanoate
QUESTION 2
Complete the following table by writing down the numbers 2.1.1 to 2.1.5 in your answer book and next
to each number the missing information:
Structural formula
IUPAC name
Homologous series
Methane
Alkanes
H
H
C
H
H
H
H
H
H
C
C
C
H
H
H
Cl
2.3
HO
H
H
C
C
H
H
H
2.1
2.2
Ethyne
2.4
Ethanol
2.5
[10]
QUESTION 3
3.1
Each of the letters A to E represents an organic compound:
Cl
A
CnH2n
B
C2H2
C
CH3OH
E
CH3COOH
D
H
C
Cl
Cl
3.1.1
Draw the structural formula of the compound containing three carbon atoms, which is a
member of the same homologous series represented by A.
(2)
3.1.2
Give the IUPAC name for B.
3.1.3
Write down the general formula for the homologous series to which compound C belongs.(2)
3.1.4
To which homologous series does compound D belong?
3.1.5
When compound C reacts with E, the product is a compound with a fruity flavour. Give the
structural formula and the IUPAC name of this product.
(4)
[12]
3.2
The empirical formula of an ester is given as C3H6O2. If methanol is used as one of the reagents
to prepare this ester,
3.2.1
Write down the structural formula of this ester.
(3)
3.2.2
Name this ester.
(2)
3.2.3
Write down the name of the other reagent that reacted with methanol to prepare this ester. (2)
[7]
3.3
Ethanol is present in all alcoholic drinks.
3.3.1
By what process is alcohol prepared from sugar?
3.3.2
Some alcohols, like glycerol, have relatively high boiling points. Explain why this is so. (2)
[4]
(2)
(2)
(2)
QUESTION 4
Organic chemistry
4.1
Bromine reacts with butene. What type of organic reaction occurs?
4.2
Name the following molecules according to the IUPAC system of nomenclature:
4.2.1
H
H
C
4.2.2
H
C
C
H
C
Cl
H
(2)
H
H
C
C
H
C
H
Br
H
H
H
4.2.3
4.2.4
H
H
C
H
O
H
H
H
H
C
C
H
H
H
O
C
C
H
H
C
C
H
OH
H
H
(8)
4.3
Write balanced equations for the following reactions:
4.3.1
Ethene reacts with bromine
(3)
4.3.2
Ethyne gas burns in an excess of oxygen.
(3)
4.4
Give and explain the trend in the respective boiling points of members of the alkanes.
(3)
[19]
TOTAL: 72 MARKS