Aristo Book 5 experiment answer

HKDSE CHEMISTRY – A Modern View (Chemistry)
Experiment Workbook 5
Suggested answers

Chapter 52 Importance of industrial processes
Chapter 53 Rate equation
Experiment 53.1 Determining the rate equation of a reaction using method of initial rate (A microscale experiment)
1
Chapter 54 Activation energy
Experiment 54.1 Determining the activation energy of a chemical reaction
3
Chapter 55 Catalysis and industrial processes
Experiment 55.1 Investigating the action of a catalyst
6
Experiment 55.2 Investigating homogeneous catalysis
8
Experiment 55.3 Investigating ways to change the rate of a reaction with a suitable catalyst
9
Experiment 55.3 Sample laboratory report
13
Experiment 55.4 Preparing ethanol by fermentation
16
Chapter 56 Industrial processes
Chapter 57 Green chemistry for industrial processes

Chapter 53 Rate equation

Experiment 53.1 Determining the rate equation of a reaction using method of initial rate (A microscale experiment)

7. and 11.(a)
Well number
1
2
3
4
5
6
7
8
Number of drops of 0.5 M Na2S2O3(aq)
10
9
8
7
6
5
4
3
Time, t (s)
14.2
15.8
17.8
20.4
23.8
28.6
35.7
47.6 (s1)
0.070
0.063
0.056
0.049
0.042
0.035
0.028
0.021

10. and 12.(a)
Well number
1
2
3
4
5
6
7
8
Number of drops of 1.0 M H2SO4(aq)
10
9
8
7
6
5
4
3
Time, t (s)
59.4
59.7
60.0
60.7
59.9
60.0
61.0
60.5 (s1)
0.017
0.017
0.017
0.016
0.017
0.017
0.016
0.017

11. (a) inversely (b)

(c) 1

12. (b) 0 (c) From the results in Table 53.2, the readings of time are close, indicating that the reaction is of zeroth order with respect to H+(aq).

13. Rate = k[S2O32(aq)]

14. S2O32(aq) + 2H+(aq)  S(s) + SO2(g) + H2O(l)

15. In this experiment, the time for the formation of a fixed, but small amount of insoluble sulphur precipitate is measured. The shorter the time, the faster is the reaction. It is assumed that the extent of reaction is still small when the time is recorded, so that the time recorded can be used as a measurement of initial rate of the reaction.
Chapter 54