Ionic EquilibriumHard
Question
What concentration of free CN– must be maintained in a solution that is 1.8 M-AgNO3 and 0.16 M-NaCl to prevent AgCl from precipitating? The value of Kf for Ag(CN)2− = 6.4 × 1017 and Ksp for AgCl = 1.8 × 10–10.
Options
A.2.5 × 10−9 M
B.5 × 10–5 M
C.2.5 × 10−5 M
D.1 × 10−4 M
Solution
To prevent precipitation of AgCl, the concentration of Ag+ needed in solution
$= \frac{K_{sp}(AgCl)}{\left( Cl^{-} \right)} = \frac{1.8 \times 10^{- 10}}{0.16} < < 1.8\text{ M}$
Hence, almost all Ag+ ion must form complete with CN– ions.
$Ag^{+} + 2CN^{-} \rightleftharpoons Ag(CN)_{2}^{-};K_{f} = 6.4 \times 10^{17} $$$\frac{1.8 \times 10^{- 10}}{0.16}M\text{CM1.8 M}$$
Create a free account to view solution
View Solution FreeMore Ionic Equilibrium Questions
A volume of 2.5 ml of 2/5 M weak monoacidic base (Kb = 1 × 10−12 at 25o C) is titrated with (2/15) M-HCl in water at 25o...The solubility product of AgCl is 10-10. The minimum volume (in L) of water required to dissolve 1.722 mg of AgCl is (mo...Slaked lime, Ca(OH)2 is used extensively in sewage treatment. What is the maximum pH that can be established in Ca(OH)2 ...If valence factor (n-factor) of compound NaHC2O4.2H2 C2O4 .3K2C2O4. 4Al2(C2O4)3.3FeC2O4 in acid base titration is x and ...Which of the following properties given in pair are shown by sulphurdioxide :-...