Molar solubility of AgCl in 0.0012 M NH3

Molar solubility of AgCl in 0.0012 M NH3

 

 

What is the molar solubility of AgCl in 0.50 M NH3?

Ksp for AgCl is 10^-10 and the Kf for Ag(NH3)2^+ is 10^8

 

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AgCl(s) ⇌ Ag^+(aq) + Cl^-(aq)

Ksp = [Ag^+][Cl^-] = 10^-10

 

Ag^+(aq) + 2NH3(aq) ⇌ Ag(NH3)2^+(aq)

Kf = [Ag(NH3)2^+] / [Ag^+][NH3]^2 = 10^8

 

 

AgCl(s) + 2NH3(aq) ⇌ Ag(NH3)2^+(aq) + Cl^-(aq)

Keq = [Ag(NH3)2^+][Cl^-] / [NH3]^2

= Ksp × Kf

= (10^(-10)) × (10^8)

= 0.01

 

 

평형에서,

AgCl(s) + 2NH3(aq) .. ⇌ .. Ag(NH3)2^+(aq) + Cl^-(aq)

......... 0.0012-2x ....... x .............. x

 

 

Keq = [Ag(NH3)2^+][Cl^-] / [NH3]^2

= x^2 / (0.0012-2x)^2 = 0.01

 

(x / (0.0012-2x))^2 = 00.01

x / (0.0012-2x) = (0.01)^(1/2) = 0.1

x = 0.00012 – 0.2x

1.2x = 0.00012

x = 0.00012 / 1.2

= 0.0001

= 10^-4 M = [Cl^-] = [AgCl]

 

 

답: 10^-4 M

 

 

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