Page 23 - Ranger SPM 2022 Chemistry

Chemistry SPM Chapter 2 Carbon Compound
(b) Halogenation (ii) Pressure: 60 atm
• Bromine solution reacts (iii) Catalyst: Phosphoric acid
with ethene at room H PO
3
4
temperature to produce 1,2- • C H (g) + H O(g) 300 C,
4
2
2
o
dibromoethane. 60 atm
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• Addition of bromine to alkene C H OH(l)
is known as bromination. 2 5
• C H (g) + Br (aq) → C H Br (l) H H H H
2
2
2
2
4
4
& &
& &
3
H H H H H!C"C!H + H!O!H H PO 4 H!C!C!H
& & & & 300 °C, 60 atm & &
H!C"C!H + Br!Br H!C!C!H H O!H
& &
Br Br (e) Oxidation
• Ethene reacts with • Ethene reacts with acidified
chlorine gas to produce potassium manganate(VII)
1,2-dichloroethane. solution to produce
• Addition of chlorine to alkene ethane-1,2-diol.
is known as chlorination. • Dilute sulphuric acid is added
• C H (g) + Cl (g) → C H Cl (g) as a catalyst in this oxidation
4
2
2
2
2
4
reaction.
H H H H • During the reaction, the
& & & &
H!C"C!H + Cl!Cl H!C!C!H purple colour of acidified
& & potassium manganate(VII)
Cl Cl solution turns colourless.
(c) Addition of hydrogen halides • C H (g) + H O(l) + [O]
4
2
2
(HCl, HBr, HI) KMnO /H + C H (OH) (l)
4
• Ethene reacts with hydrogen 2 4 2
chloride to produce H H H H
chloroethane, an example of & & KMnO /H + & &
4
haloalkane. H!C"C!H + H!O!H + [O] H!C!C!H

& &
• C H (g) + HCl(g) → C H Cl(g) O O
2
2
4
5
& &
H H H H H H
& & & &
H!C"C!H + H!Cl H!C!C!H (f) Addition polymerisation
& & • Ethene is normally used
H Cl as a monomer in additional
(d) Hydration polymerisation to produce
• A well-known industrial various types of plastic in our
Form 5
process to manufacture daily lives.
alcohols. - Ethene is heated under
• Ethene reacts with hot specific conditions:
steam in specific conditions (i) Temperature: 200 °C
to produce ethanol. (ii) Pressure: 1200 atm
• Specific conditions needed:
(i) Temperature: 300 °C
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02.5 RANGER SPM CHEMISTRY 2P.indd 152 29/03/2022 2:28 PM