Kinetics 4

Answer to Prob 19, L4, p21

slope = -12480 K

Answer to Prob 20, L4, p21

1.73 x 10-19J

5.6 x 10-21 J

a)
0.79 x 106 at 40°C
5.2 x 106 at 55°

b) 205 m/s

from the graph, c = 31.60 = ln A

a)
247.7 m/s at 40°C
259.3 m/s at 70°C

b)
247.7 x 10-16 m3

2.593 x 10-16 m3

c)
1.49 x 108

1.562 x 108

a) at 40°C, N = 2.345 x 1025 m-3 at 70°C, N = 2.14 x 1025 m-3

b) ZAA =6.81 x 1034 m-3.s-1 ZAA = 5.94 x 1034 m-3.s-1

c) ZAA at 70°C is less than ZAA at 40°C

Answer to Prob 26, L5, p31

c = 302.6 m/s
k
= 2.07 x 10-7 L.mol-1.s-1

Answer to Prob 27, L5, p32

Ea is an empirical value (measured from experiment), i.e. not calculated from scratch.

Doesn’t apply to reactions in solution
quantum effects are ignored
internal motions of atoms in the molecules are ignored.

Answer to Prob 30, L6, p37

5.69 x 1012 s-1
6.21 x 1012 s-1
9.86 x 1012 s-1

Answer to Prob 32, L6, p38

Only D , D , D , and temperature.

Answer to Prob 33, L6, p39

Ea » 83 kJ/mol ; D » 80.6 kJ/mol

Answer to Prob 34, L6, p39

61.9 kJ/mol , 61.5 kJ/mol i.e. D = 62 +/- 2 kJ/mol

a) 2nd ord eq.: calculate the reciprocal of reactant conc’n at various times, and plot against time. slope equals 2k, the rate constant.

2nd ord unequal calculate the y values according to the eq’n 5, p10, and plot against time. Slope = (a-b) x 2k