Spectrophotometric Determination of Iron(II) and Cobalt(II) by Direct, Derivative, and Simultaneous Methods Using 2-Hydroxy-1-Naphthaldehyde-p-Hydroxybenzoichydrazone
Table 1
Tolerance limits of foreign ions, Amount of Fe(II) taken = 0.558 μg mL−1 pH = 5.0.
Foreign ion
Tolerance limit (μg mL−1)
Foreign ion
Tolerance limit (μg mL−1)
Foreign ion
Tolerance limit (μg mL−1)
Sulphate
1440
Na(I)
1565
La(III)
18
Iodide
1303
Mg(II)
1460
Ag(I)
15
Phosphate
1424
Ca(II)
1440
Hg(II)
16
Thiosulphate
1424
K(I)
1300
U(VI)
6,60a
Tartrate
1414
Ba(II)
1260
Mn(II)
4,55a
Thiourea
1140
Pd(II)
63
Th(IV)
3,50a
Bromide
1138
Cd(II)
45
In(III)
4,60a
Nitrate
930
Bi(III)
42
Sn(II)
<1,50a
Carbonate
900
W(VI)
37
Co(II)
<1,55a
Thiocyanate
870
Hf(IV)
36
Ni(II)
<1,60b
Chloride
531
Ce(IV)
28
Zn(II)
<1,80b
Fluoride
285
Cr(VI)
27
Al(III)
<1,45a
EDTA
124
Mo(VI)
22
Cu(II)
<1,50a
Citrate
115
Zr(IV)
19
Oxalate
95
Sr(II)
18
In the presence of μg of tartrate, μg of thiocyanate.