7 [
]
[ ]
R0
R
k
t
−
=
[
]
[
]0
1/2
1 R
At
,
R
2
t
=t
=
The rate constant at t1/2   becomes
[
]
[
]
0
0
1/2
1/2
R
R
k
−t
=
[ ]0
1/2
R
2
t
k
=
It is clear that t1/2 for a zero order reaction is directly proportional
to the initial concentration of the reactants and inversely proportional
to the rate constant For the first order reaction,
[
]
[
]
0
2 303
R
log
R
k
t
=
(3