JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
During the qualitative analysis of \(SO _3^{2-}\) using dilute \(H _2 SO _4, SO _2\) gas is evolved which turns \(K _2 Cr _2 O _7\) solution (acidified with dilute \(H _2 SO _4\) ):
- A Black
- B Red
- C Green
- D Blue
Answer & Solution
Correct Answer
(C) Green
Step-by-step Solution
Detailed explanation
\(Cr _2 O _7^{2-}+ SO _3^{2-} \stackrel{ H ^{+}}{\longrightarrow} \underset{\text { Green }}{ Cr ^{3+}}+ SO _4^{2-}\)
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