ExamBro
ExamBro
CUET · CHEMISTRY · PYQ PAPER 2023

In which of the following cases is there a change in oxidation number?

  1. A Aqueous solution of \(CrO _4^{2-}\) is acidified
  2. B \(SO _2\) gas is passed through acidified \(Cr _2 O _7^{2-}\) solution
  3. C \(Cr _2 O _7^{2-}\) solution is made allcaline
  4. D \(CrO _2 Cl _2\) is dissolved in NaOH
Verified Solution

Answer & Solution

Correct Answer

(B) \(SO _2\) gas is passed through acidified \(Cr _2 O _7^{2-}\) solution

Step-by-step Solution

Detailed explanation

In \(Cr_2O_7^{2-}\), Cr oxidation state: \(2x + 7(-2) = -2 \Rightarrow x = +6\). In \(SO_2\), S oxidation state: \(y + 2(-2) = 0 \Rightarrow y = +4\). When \(SO_2\) is passed through acidified \(Cr_2O_7^{2-}\) solution, \(Cr_2O_7^{2-}\) is reduced to \(Cr^{3+}\) and \(SO_2\) is…
From CUET
Explore more questions on app