Page 134 - [B._MURPHY,_C._MURPHY,_B._HATHAWAY]_A_working_meth

118 Chapter 8

Rate k[AI2
* kdt

=+ kJdt

1

A
since JYdx = -
n+l
I
At t = 0, [A] = [&] = the initial concentration + c =

1
=kt +-
- 1
[A1 [A01
y = mx + c (second-order reaction)

This is also the equation of a line, i.e. if the reaction obeys second-
order kinetics, a plot of l/[A] versus t should yield a straight line
graph, of slope m = k and intercept c = l/[Ao].

Units of k for a second-order reaction of the form A + Products:
1 1
-=kt +-
[A1 [A01

=+ units of k are M-'s-'.

HALF-LIFE
The hay-fife is the time it takes one-half of a reactant to be consumed
in a reaction (Figure 8.3).