The data corresponding to the first-order decomposition of a substance A at 250 K are given on page 4 of the exam. However, there are some problems with the information. Specifically, someone tinkered with the experimental apparatus, raising the temperature to 273 K at a certain time, and later raising it again to another, unspecified temperature. Your job is to complete the following:
Determine the times where the temperature was raised to 273 K and the unspecified temperature.
Determine the specific reaction rate coefficient for the decomposition at 273 K
Determine the activation energy for the reaction.
Determine the unspecified final temperature that the experimental system was set to.
Assuming this is a unimolecular reaction, use the Arrhenius equation information given above (and some surprisingly direct equations in your text) to determine H‡, S ‡ and G‡ for the transition state species at the final, unspecified temperature (that you should know by now).
Time (min)
[A] (mmol L-1)
0
10
4.21053
9.66877
8.42105
9.34851
12.63158
9.03885
16.84211
8.73946
21.05263
8.44998
25.26316
8.17009
29.47368
7.89947
33.68421
7.63781
37.89474
7.38482
42.10526
7.14022
46.31579
6.90371
50.52632
6.67504
54.73684
6.45394
58.94737
6.24016
63.15789
6.03347
67.36842
5.83362
71.57895
5.64039
75.78947
5.45356
80
5.27292
84
4.99374
88
4.72933
92
4.47893
96
4.24179
100
4.0172
104
3.8045
108
3.60306
112
3.41229
116
3.23162
120
3.06052
124
2.714
128
2.40672
132
2.13423
136
1.89259
140
1.67831
144
1.48829
148
1.31978
152
1.17035
156
1.03784
160
0.92034
164
0.81614
168
0.72373
172
0.64179
176
0.56913
180
0.50469
184
0.44755
188
0.39687
192
0.35194
196
0.31209
200
0.27676
Determine the molarity of Sr2+ in a saturated aqueous solution of calcium phosphate (Sr3(PO4)2, Ksp = 1.0 × 10-31) at 298 K.
First, assume that the activity coefficient of all species in solution = 1.
Using…