aA þ bB ! pP þ qQ þ . . .
ð2:1:7Þ
occurring under constant-volume conditions, without an appreciable build-up of
reaction intermediates, the rate of reaction is defined as:
v ¼ À
1
a
d½A
dt
¼ À
1
b
d½B
dt
¼
1
p
d½P
dt
¼
1
q
d½Q
dt
ð2:1:8aÞ
or
v ¼ À
1
a
c A
dt
¼ À
1
b
c B
dt
¼
1
p
c P
dt
¼
1
q
c Q
dt
ð2:1:8bÞ
where symbols placed inside square brackets or c in (2.1.8b) denote amount (or
amount of substance) concentrations (conventionally expressed in units of mol
dm
−3 ). The symbols R and r are also commonly used in place of m.’ The author will
use the symbol r.
The author usually follows to symbols used in [2].
– Amount of substance concentration is the number of moles n divided by volume,
for example,
c B ¼
n B
V
mol=dm
3 mol=1; mol=cm
3
À
Á
The mole is the amount of substance of a system which contains as many
elementary entities (atoms, molecules, ions and so on) as there are atoms in
0.012 kg of
12 C atoms [1] or amount of elementary entities (species) equal to the
Avogadro number, N A = 6:02 Á 10
23
entities/mol.
Another definition of concentration is preferably for use if one deals with processes in which atoms or radicals participate. It is rather strange to write ‘concentration of O(
1 D) atoms is equal to n mol/l.’ It is much more convenient to
measure concentration as the amount of species N in unit volume:
N B
V
¼ ½B ¼ c B Á N A species=cm
3
À
Á
Below, the author uses the species/cm
3 units of concentration. For these units,
the rate of a process is defined as:
r ¼ À
1
v i
d A i
½
dt
¼
1
v 0
k
d A
0
k
 Ã
dt
;
ð2:1:8cÞ
2.1 Rates of Reaction, Collisional, and Spontaneous Processes …
7
ð2:1:7Þ
occurring under constant-volume conditions, without an appreciable build-up of
reaction intermediates, the rate of reaction is defined as:
v ¼ À
1
a
d½A
dt
¼ À
1
b
d½B
dt
¼
1
p
d½P
dt
¼
1
q
d½Q
dt
ð2:1:8aÞ
or
v ¼ À
1
a
c A
dt
¼ À
1
b
c B
dt
¼
1
p
c P
dt
¼
1
q
c Q
dt
ð2:1:8bÞ
where symbols placed inside square brackets or c in (2.1.8b) denote amount (or
amount of substance) concentrations (conventionally expressed in units of mol
dm
−3 ). The symbols R and r are also commonly used in place of m.’ The author will
use the symbol r.
The author usually follows to symbols used in [2].
– Amount of substance concentration is the number of moles n divided by volume,
for example,
c B ¼
n B
V
mol=dm
3 mol=1; mol=cm
3
À
Á
The mole is the amount of substance of a system which contains as many
elementary entities (atoms, molecules, ions and so on) as there are atoms in
0.012 kg of
12 C atoms [1] or amount of elementary entities (species) equal to the
Avogadro number, N A = 6:02 Á 10
23
entities/mol.
Another definition of concentration is preferably for use if one deals with processes in which atoms or radicals participate. It is rather strange to write ‘concentration of O(
1 D) atoms is equal to n mol/l.’ It is much more convenient to
measure concentration as the amount of species N in unit volume:
N B
V
¼ ½B ¼ c B Á N A species=cm
3
À
Á
Below, the author uses the species/cm
3 units of concentration. For these units,
the rate of a process is defined as:
r ¼ À
1
v i
d A i
½
dt
¼
1
v 0
k
d A
0
k
 Ã
dt
;
ð2:1:8cÞ
2.1 Rates of Reaction, Collisional, and Spontaneous Processes …
7