Page 19 - 1202 Question Bank Chemistry Form 5 KSSM

PAPER 3

Table 1 shows the result of an experiment to investigate the difference in properties between natural rubber and
vulcanised rubber.

Rubber P Rubber Q

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Initial length (cm) 8.0 cm 8.0 cm

7
Clip Clip
0 8 0
2 2
3 3
9
4 4
5 5
10
Length with 200 g Rubber P 6 Rubber Q 6
7 7
weight (cm) 8 11 8
9 9
10 12 10
11 11
12 12
Weight 200 g Weight 200 g

8.0 cm
Length after weight
is withdrawn (cm) 10.0 cm

Table 1
Based on Table 1, plan an experiment in the laboratory to investigate the elasticity or strength of unvulcanised
and vulcanised rubber.
1. State the variables for this experiment. [2 marks]
(a) Manipulated variable:

(b) Responding variable:

93
• Vulcanisations produce sulphur cross linkages between rubber polymer chains.
• Vulcanisations produce rubber that is more elastic and of better quality. SOS TIP