Question

The increasing order of Ag⁺ ion concentration in

I. Saturated solution of AgCl

II. Saturated solution of AgI

III. 1(M) Ag(NH₃)₂⁺ in 0.1 (M) NH₃

IV. 1(M) Ag(CN)₂^– in 0.1 (M) KCN

Given: K_sp of AgCl = 10^–10 ;K_sp of AgI = 10^–16

K_instab of Ag(NH₃)₂⁺ = 10^–8

K_instab of Ag(CN)₂^– = 10^–21

• A. I < II < III < IV
• B. IV < III < II < I
• C. IV < II < III < I
• D. IV < II < I < III

Answer 1

Answer: (C)

IV < II < III < I

Answer 2

In saturated solution AgCl, [Ag⁺] = 10^–5(M)

In saturated solution AgI ,[Ag⁺] = 10^–8(M)

In the solution containing Ag(NH₃)₂⁺ & NH₃ ,

10^–8 = $\frac { \left[ \mathrm { Ag } ^ { + } \right] ( 0.1 ) ^ { 2 } } { 1 }$ or [Ag⁺] = 10^–6 (M)

In the solution containing Ag(CN)₂^– & KCN

10^–21 = $\frac { \left[ \mathrm { Ag } ^ { + } \right] ( 0.1 ) ^ { 2 } } { 1 }$ or [Ag⁺] = 10^–19 (M)