In: Chemistry
1.Given the following data for the reaction A ® B, determine the activation energy, Ea, of the reaction.
| 
 k (M/s)  | 
 T (K)  | 
| 
 0.681  | 
 500  | 
| 
 0.715  | 
 1,000  | 
| a. | 
 2.05 ´ 10–2 kJ/mol  | 
|
| b. | 
 405 J/mol  | 
|
| c. | 
 6.90 J/mol  | 
|
| d. | 
 48.7 J/mol  | 
|
| e. | 
 9.95 kJ/mol  | 
2. The mechanism for the reaction 2H2O2(aq) ® 2H2O(l) + O2(g) in the presence of I–(aq) is proposed to be:
Step 1: H2O2(aq) +
I–(aq) ® H2O(l) +
OI–(aq)
Step 2: H2O2(aq) +
OI–(aq) ® H2O(l) +
O2(g) + I–(aq)
Which of the following species is an intermediate?
| a. | 
 I–  | 
|
| b. | 
 H2O2  | 
|
| c. | 
 H2O  | 
|
| d. | 
 OI–  | 
|
| e. | 
 This mechanism has no intermediates.  | 
K1   = 0.681M/sec
T1   = 500K
K2    = 0.715M/sec
T2    = 1000K
logK2/K1   = Ea/2.303R[1/T1 -1/T2]
log0.715/0.681   = Ea/2.303*8.314 [1/500 -1/1000]
0.0211          =
Ea/19.147[0.002-0.001]
Ea              
= 0.0211*19.147/0.001   = 405J/mole
b. 405 J/mol>>>>>answer
2. Step 1: H2O2(aq) +
I–(aq) ---------->
H2O(l) + OI–(aq)
Step 2: H2O2(aq) +
OI–(aq)
--------------->H2O(l) +
O2(g) + I–(aq)
OI^- is intermediate
d. OI– >>>>>answer