MHT CET202311 May 2023Morning ShiftChemistryAminesActual
Which of the following salts turns red litmus blue in its aqueous solution?
Options
- ANH ₄ NO ₃
- BNH ₄ Cl
- CNH ₄ CN
- DNH ₄ ~F
Correct answer
C. NH ₄ CN
Step-by-step solution
NH ₄ CN is the salt of weak acid HCN ( K _ a =4.0 10⁻¹⁰ ) and weak base NH ₄ OH ( K _ b =1.8 10⁻⁵ ) showing that K _ a < K _ b . If K _ a < K _ b , the aqueous solution of the salt will be basic. Thus, the solution of NH ₄ CN is basic and turns red litmus blue.