Spectrophotometric Determination of Iron(II) and Cobalt(II) by Direct, Derivative, and Simultaneous Methods Using 2-Hydroxy-1-Naphthaldehyde-p-Hydroxybenzoichydrazone

Table 16

Determination of iron and cobalt in alloy samples.

Sample (composition)	Amount (%)				Relative error (%)
	Certified		Found (𝑛=3) ± SD
	Fe(II)	Co(II)	Fe(II)	Co(II)	Fe(II)	Co(II)
Elgiloy-M; (20 Cr; 15 Ni; 0.15 C; 2 Mn; 7 Mo;.05 Be)	15	40	14.82±0.15	39.39±0.20	1.33	1.52
Rim alloy; (17 Mo; 3Mn)	68	12	69.28±0.86	12.08±0.38	1.88	0.66
Sofcomag 25; (Fe and Co)	75	25	73.89±1.38	25.98±0.86	1.48	3.92
Sofcomag 49; (Fe and Co)	51	49	52.12±0.35	49.18±0.06	2.18	0.36