CIE iGCSE Co-Ordinated Science C11.1 Formulas and terminology Exam Style Questions Paper 4
Question
Fig. 2.1 shows the displayed formulae of some carbon compounds
(a) State which compound in Fig. 2.1 is not a hydrocarbon.
Explain your answer.
compound ……………………………………………………….
explanation ……………………………………………………………………………………………………………….
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(b) State which compound in Fig. 2.1 will decolourise aqueous bromine.
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(c) Compound D is used as a fuel.
State one other use of compound D.
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(d) Compound C is a saturated compound.
State what is meant by saturated.
(e) Compound C, C$_{3}$H$_{8}$, undergoes complete combustion in oxygen.
Construct the balanced symbol equation for this reaction.
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(f) Compound A is ethene.
Complete Fig. 2.2 to show the displayed formula of the polymer poly(ethene)
(g) The formation of poly(ethene) from ethene is an example of addition polymerisation.
Explain the differences between addition polymerisation and condensation polymerisation.
▶️Answer/Explanation
Ans: 2(a) D ;
contains oxygen / does not contain only carbon and hydrogen ;
2(b) A ;
2(c) solvent ;
2(d) contains only C-C single bonds ;
2(e) C$_{3}$H $_{8}$ + 5O$_{2}$ → 3CO$_{2}$ + 4H$_{2}$O
correct formulae (reactants in either order and products in either order) ;
balanced correctly ;
2(f)
2(g) addition polymerisation
only occurs in unsaturated monomers or monomers that contain C=C bonds/idea that involves the addition of many (identical) monomers (to make a long chained polymer)/monomers have one functional group/
forms the polymer molecule only ;
condensation polymerisation
idea that two different monomers join together/(forms the polymer molecule and one) water molecule (per linkage) /monomers have two functional groups (one at each end) ;