CIE iGCSE Co-Ordinated Science C11.2 Naming organic compounds Exam Style Questions Paper 3
Question
(a) Fig. 11.1 shows the molecular structure of ethene.
i) State the total number of atoms in a molecule of ethene.
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(ii) State the formula of ethene.
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(iii) Use Fig. 11.1 to explain why an ethene molecule is described as unsaturated.
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(iv) State the chemical test for an unsaturated hydrocarbon.
Give the observations for a positive result.
test ……………………………………………………………………………………………………………………
observations ……………………………………………………………………………………………………….
(b) (i) State the two products of the complete combustion of ethene.
1 ……………………………………………………………………………………………………………………….
2 ……………………………………………………………………………………………………………………….
(ii) Ethene is made from the breakdown of larger molecules in petroleum.
State the name of this process.
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(iii) Polymerisation of ethene produces poly(ethene).
Describe what happens to ethene molecules during polymerisation.
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▶️Answer/Explanation
Ans : 11(a)(i) 6 ;
11(a)(ii) C2H4 ;
11(a)(iii) C=C double bond ;
11(a)(iv) aqueous bromine ;
orange to colourless ;
11(b)(i) carbon dioxide ;
water ;
11(b)(ii) cracking ;
11(b)(iii) join together / make a long chain ;