Question

The correct stability order of the following diazonium salts is:

Choose the correct answer from the options given below: 
 

• A. A $>$ C $>$ D $>$ B
• B. A $>$ B $>$ C $>$ D
• C. C $>$ D $>$ B $>$ A
• D. C $>$ A $>$ D $>$ B

Hint:

Electron donating groups increase diazonium stability, while strong electron withdrawing groups decrease it.

Answer 1

The Correct Option is A

Step 1: Basic stability rule for diazonium salts.
Aryl diazonium salts are stabilized by electron donating groups on the benzene ring and destabilized by strong electron withdrawing groups. 
Step 2: Effect of substituents. 
(A) $-OCH_3$: Strong $+M$ (electron donating) effect, stabilizes diazonium ion greatly. 
(C) H: No substituent effect, moderate stability. 
(D) $-CN$: Strong $-M$ effect, reduces stability. 
(B) $-NO_2$: Very strong $-M$ and $-I$ effects, maximum destabilization. 
Step 3: Ordering stability. 
\[ \text{A (most stable)}>\text{C}>\text{D}>\text{B (least stable)} \] Step 4: Final conclusion. 
The correct stability order is A $>$ C $>$ D $>$ B, corresponding to option (1).