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Choose the correct option.
Acidified K₂Cr₂O₇ solution turns green when Na₂SO₃ is added to it. This is due to formation of:
Acidified $\text{K}_2\text{Cr}_2\text{O}_7$ solution turns green when $\text{Na}_2\text{SO}_3$ is added to it. This is due to formation of:
- (a)$\text{CrO}_4^{2-}$
- (b)$\text{Cr}_2(\text{SO}_3)_3$
- (c)$\text{Cr}_2\text{O}_3$
- (d)$\text{Cr}_2(\text{SO}_4)_3$
Answer
Answer
Correct option: (d)
Answer: (d) $\mathrm{Cr_2(SO_4)_3}$
Sulphite reduces orange $\mathrm{Cr_2O_7^{2-}}$ to green $\mathrm{Cr^{3+}}$, and is oxidised to sulphate, giving green $\mathrm{Cr_2(SO_4)_3}$.