Solutions to exercises
151
Figure 60 – The product DT
as a function of temperature
in Arrhenius coordinates.
b. The activation energy is obtained from
D
T
D e RT
E
0
a
=
−
or
.
log
log
DT
D
RT
E
2 3
a
0
=
−
c
m
The linear regression based on the experimental data gives
.
.
log DT
T
5 864
10
1 567
3
= −
+
#
^ h
which allows us to calculate E a = − 19.12 # (− 5.864)
We obtain
E a = 112 kJ mol
−1
The activation energy in eV is obtained as follows:
[ ]
[
]
E eV
E kJ mol
e N
10
a
a
Av
1
3
–
=
#
#
which gives
.
E
e V
1 16
a =
3. The electric mobility is given by u
cz e .
i
i
i i
σ
=
^
h The corresponding dimensions are
u
cm C
S cm
i
3
1
=
−
−
Because
C ≡ A s ≡ V S s
we arrive at
u
V s
cm
i
2
=
The electric mobility of a species i is thus expressed in cm
2
V
−1
s
−1
.
<
<
<
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ORJ'7>'7LQFP
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—
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151
Figure 60 – The product DT
as a function of temperature
in Arrhenius coordinates.
b. The activation energy is obtained from
D
T
D e RT
E
0
a
=
−
or
.
log
log
DT
D
RT
E
2 3
a
0
=
−
c
m
The linear regression based on the experimental data gives
.
.
log DT
T
5 864
10
1 567
3
= −
+
#
^ h
which allows us to calculate E a = − 19.12 # (− 5.864)
We obtain
E a = 112 kJ mol
−1
The activation energy in eV is obtained as follows:
[ ]
[
]
E eV
E kJ mol
e N
10
a
a
Av
1
3
–
=
#
#
which gives
.
E
e V
1 16
a =
3. The electric mobility is given by u
cz e .
i
i
i i
σ
=
^
h The corresponding dimensions are
u
cm C
S cm
i
3
1
=
−
−
Because
C ≡ A s ≡ V S s
we arrive at
u
V s
cm
i
2
=
The electric mobility of a species i is thus expressed in cm
2
V
−1
s
−1
.
<
<
<
<
ORJ'7>'7LQFP
V
<
.@
—
7>.@