Question

Which of the following is the correct decreasing order of oxidizing power of perhalate ions?

• A. \(\text{BrO}_4^- < \text{IO}_4^- < \text{ClO}_4^-\)
• B. \(\text{IO}_4^- > \text{BrO}_4^- > \text{ClO}_4^-\)
• C. \(\text{IO}_4^- < \text{BrO}_4^- < \text{ClO}_4^-\)
• D. \(\text{BrO}_4^- > \text{IO}_4^- > \text{ClO}_4^-\)

Hint:

Perbromate is the strongest oxidiser among perhalates because of the poor stability of Br in the +7 state.

Answer 1

The Correct Option is D

Step 1: Recall the known order.
The syllabus order for the oxidising power of perhalates is perbromate first, then periodate, then perchlorate.

Step 2: Explain with periodic trends.
The +7 state of bromine is destabilised by the 3d electrons that shield the nucleus poorly. That makes perbromate a very strong oxidant.

Step 3: Pick the option.
The order $\text{BrO}_4^- > \text{IO}_4^- > \text{ClO}_4^-$ is option (D).

Final Answer:
Option (D). \[ \boxed{\text{BrO}_4^- > \text{IO}_4^- > \text{ClO}_4^-} \]