In the atomic absorption spectroscopic estimation of Fe(III) using $\mathrm{O_2}$ / $\mathrm{H_2}$ flame, the absorbance decreases with the addition of:
(a)$\mathrm{CO_3^{2+}}$
(b)$\mathrm{SO_4^{2-}}$
(c)EDTA
(d)$\mathrm{Cl^-}$
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
Sulfate forms thermally stable (refractory) iron compounds in the flame, reducing free Fe atoms — a chemical interference that lowers absorbance (b); EDTA acts as a protecting agent instead.