文档介绍：Reaction ics (2)
Xuan Cheng
Xiamen University
Physical Chemistry
1
Order
Reaction
Rate Law
t1/2
0
A P
1
A P
2
A P
n2
A P
Simple Order Reactions
Physical Chemistry
Reaction ics
2
plex Reactions
Physical Chemistry
Reversible reaction
Consecutive reaction
Opposing reaction
Competing reaction
Parallel reaction
kb
(1)
(2)
(3)
Reaction ics
3
Physical Chemistry
Reversible First-Order Reactions
Consider the reverse reaction (opposing reaction)
kb
()
the first order in both forward and back directions
Reaction ics
4
Physical Chemistry
()
()
Reversible First-Order Reactions
Reaction ics
5
Physical Chemistry
At equilibrium,
Reversible First-Order Reactions
()
and
()
()
Reaction ics
6
()*
()
Physical Chemistry
Reversible First-Order Reactions
[A]/[A]o
[C]/[A]o
kf / kb=2
A C
jt
Fig.
When [A]eq=0, kb=0
[A]/[A]o
t
Fig. (a)
Reaction ics
7
Physical Chemistry
Consecutive First-Order Reactions
Consider two consecutive irreversible first-order reactions
()
()
Reaction ics
8
Physical Chemistry
Let only A be present in the system at t = 0
()
Consecutive First-Order Reactions
()
()
()
()
()
Integration
Reaction ics
?
9
Physical Chemistry
Consecutive First-Order Reactions
At all times (conservation of matter)
()
()
()
Reaction ics
10