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