Page 59 - ACE YR IGCSE A TOP APPROACH TO CHEM

(e) (i) H H H H Physical property [1]
• Tough / strong
C C C C • Insoluble in water
H Cl H Cl • Light
Two repeat units are shown. [1] Or
C–C single bonds [1] Use [1]
• Making tents
(ii) Any one from: [1]
• Water pipes Physical property [1]
• Wellingtons • Tough / strong
• Hoses • Insoluble in water
• Covering for electrical cables • Light
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Or
(f) (i) Do not decompose [1]
by microbes [1] Use [1]
• Making curtains
(ii) Any two from: [2] Physical property [1]
• Do not conduct electricity • Tough / strong
• Unreactive • Insoluble in water
• Light • Light
• Hard / strong
• Not flammable (c) (i) O O
(iii) Any two from: [2] C C O O
• Fill up landfill sites [1]
• Danger to animals (ii) H O O H [1]
• Clog up drains / cause flooding
• Produce greenhouse gases O O
• Produce toxic gases when burnt H O C C O H [1]
• Cause visual pollution
7 (a) Condensation polymerisation (iii) Any one from: [1]
Two types of monomers are used. [1] • Clothing
• Making thread
Addition polymerisation
One type of monomer is used. [1] 8 (a) Amino acid [1]
or (b) O H O H O H
Condensation polymerisation C N C N C N
Make one long chain of molecules and eliminate
one small molecule. [1] Correct amide linkage [1]
Three different amino acids [1]
Addition polymerisation Draw the arm to show continuous [1]
Only one long chain of molecules is formed. [1]
(c) Amide linkage [1]
(b) (i) H H O O
(d) Nylon is made up of two different monomers.
N N C C Protein is made up of more than two types of
monomers. [1]
Correct amide linkage [1] Both sides of the functional group are the same
Draw the arm to show continuous [1] for each monomer in nylon, but monomers in
Correct structure of monomer [1] protein have two different types of functional
(ii) Amide linkage [1] groups in one molecule. [1]
(iii) HCl / hydrochloric acid / hydrogen (e) (i) Breaking down of a molecule [1]
chloride [1] using water [1]
(iv) Use [1] (ii) Protease [1]
• Making ropes (iii) Concentrated hydrochloric acid [1]
Physical property [1] 6 M hydrochloric acid is used in the laboratory
• Tough / strong to hydrolyse proteins. It is boiled for 24 hours.
Or (iv) Paper chromatography [1]
Use [1] 9 (a) A long-chain organic compound [1]
• Making fishing nets and lines which is made of glucose [1]

Answers 171

Answers.indd 171 3/4/22 3:54 PM