324-325 / 3107
Chemical standard (Fricke)
Determine
M = mole Fe
3+
/liter
- Fe
3+
exhibits strong absorption peak at
= 304 nm, Fe
2+
not
- measure UV transmissions through Fricke samples:
Fe
2+
in H
2
O
uv
I
0
before irradiation:
Fe
2+
and
Fe
3+
in H
2
O
uv
I
after irradiation:
M
=
log(I
0
/I)
·L
= 2187 liter mole
-1
cm
-1