Question

Solubility of $ AgCN $ is maximum in:
(A) Acidic buffer solution
(B) Basic buffer solution
(C) In pure water
(D) Equal in all solution

Answer 1

Hint: The concentration of the solid that can dissolve in solution (expressed in moles per L) when in equilibrium with an excess amount of solid. On the other hand it can also be defined as the maximum concentration (in terms of the solid) of a substance that can exist in solution before precipitation begins if sufficiently seeded.

Complete step by step solution:
The buffer solution is a solution able to maintain its Hydrogen ion concentration (pH) with only minor changes on the dilution or addition of a small amount of either acid or base. Buffer Solutions are used in fermentation, food preservatives, drug delivery, electroplating, printing, the activity of enzymes, and blood oxygen-carrying capacity need specific hydrogen ion concentration.
Acidic buffers: As the name suggests, these solutions are used to maintain acidic environments. Acid buffer has acidic pH and is prepared by mixing a weak acid and its salt with a strong base. An aqueous solution of an equal concentration of acetic acid and sodium acetate has a pH of $ 4.74 $ .
 $ AgCN + HA \to HCN $
Due to this reaction, the reaction shifts forward, and the solubility of silver cyanide increases.
So $ AgCN $ has maximum solubility in an acidic buffer solution.

Note:
Silver cyanide is the chemical compound with the formula $ AgCN $ . It is a white solid that precipitates upon treatment of solutions containing Ag+ with cyanide, which is used in some schemes to recover silver from the solution. Silver cyanide is used in silver-plating.