Solubility Equilibria Of Sparingly Soluble Salts

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) : Strong (electron donating) effect, stabilizes diazonium ion greatly.
(C) H: No substituent effect, moderate stability.
(D) : Strong effect, reduces stability.
(B) : Very strong and effects, maximum destabilization.
Step 3: Ordering stability.
Step 4: Final conclusion.
The correct stability order is A C D B, corresponding to option (1).

Step 1: Stability principle for carbanions.
Carbanions are stabilized by electron withdrawing groups and destabilized by electron donating groups.
Step 2: Analysing substituent effects.
(IV) : Strong and effect, maximum stabilization.
(I) : effect dominates, stabilizing the carbanion.
(II) H: No substituent effect, moderate stability.
(V) : effect, destabilizes carbanion.
(III) : Strong effect, maximum destabilization.
Step 3: Ordering stability.
Step 4: Final conclusion.
The correct decreasing order of stability is IV I II V III, corresponding to option (1).