
55-51Electrochemical Composition Measurement
the latter one with hydrogen ions by the following reaction:
H O O H
2
1
2
2
2 2⇔ + +
+ −
( )g e
(5
5
.62
)
A working (generator) electrode of silver as anode oers the determination of Cl
−
, Br
−
, I
−
, and mercap-
tans
i
n
s
olution(s)
. F
or
b
romide,
t
he
r
eaction
b
ecomes
Ag Br AgBr( )+ ⇔ +
− −
( )s s e
(55.63)
Similar
pr
ecipitation
an
d
co
mplex-formation
ti
trations
as we
ll
as ox
idation–reduction
ti
trations
ar
e
described in Skoog et al. (2007).
Co
ulometric
ti
trations
po
ssess
so
me
pr
actical
ad
vantages:
no st
andard
so
lutions
ar
e
re
quired
an
d
un
stable
re
agents
ca
n
be ge
nerated
or co
nsumed
im
mediately,
sm
all
am
ounts
of ti
tr ...