Question

Potassium dichromate is used:

• A. in electroplating
• B. as a reducing agent
• C. as an oxidising agent to oxidise ferrous ions into ferric ions
• D. as an insecticide

Hint:

$K_{2}Cr_{2}O_{7}$ and $KMnO_{4}$ are standard lab oxidants.

Answer 1

The Correct Option is C

Step 1: Concept
Potassium dichromate ($K_{2}Cr_{2}O_{7}$) is a powerful oxidising agent in acidic media.
Step 2: Analysis
It accepts electrons: $Cr_{2}O_{7}^{2-} + 14H^{+} + 6e^{-} \rightarrow 2Cr^{3+} + 7H_{2}O$. It oxidises $Fe^{2+}$ to $Fe^{3+}$.
Step 3: Conclusion
Its primary chemical use listed is as an oxidising agent.
Final Answer: (C)