JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
A paper dipped in a dil. \(H_2SO_4\) solution of '\(X\)' upon treatment with \(SO_2\) gas turns into green. The compound '\(X\)' is :
- A KI-starch
- B \(KMnO_4\)
- C \(Pb(CH_3COO)_2\)
- D \(K_2Cr_2O_7\)
Answer & Solution
Correct Answer
(D) \(K_2Cr_2O_7\)
Step-by-step Solution
Detailed explanation
\(SO_2\) gas acts as a reducing agent. When a paper dipped in an acidified solution of potassium dichromate (\(K_2Cr_2O_7\)) is exposed to \(SO_2\) gas, the orange-colored dichromate ion (\(Cr_2O_7^{2-}\)) is reduced to the green-colored chromium(III) ion (\(Cr^{3+}\)). The…
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