Question

Silver is often extracted from ores as K[Ag(CN)₂] and then recovered by the following reaction.

2K[Ag(CN)₂](aq) + Zn(s) → 2 Ag(s) +Zn(CN)₂(aq)+2KCN(aq)

(a) How many molecules of Zn(CN)2 are produced by the reaction of 35.90 g of K[Ag(CN)₂]?
(b) What mass (in g) of Zn(CN)₂ is produced by the reaction of 35.90 g of K[Ag(CN)₂]?

Answer 1

To calculate the number of Zn(CN)2 molecules and the mass produced, we need to use the stoichiometry and molar masses.

Step-by-step explanation:

In the given reaction, 2K[Ag(CN)₂](aq) + Zn(s) → 2Ag(s) + Zn(CN)₂(aq) + 2KCN(aq), the stoichiometry can be used to determine the number of Zn(CN)2 molecules produced and the mass of Zn(CN)2 produced.

(a) To calculate the number of molecules of Zn(CN)2 produced, we first need to find the moles of K[Ag(CN)₂] using its molar mass. Then, using the stoichiometry, we can determine the number of molecules of Zn(CN)2 that correspond to those moles.

(b) To calculate the mass of Zn(CN)2 produced, we need to use the molar mass of Zn(CN)2 and the moles of K[Ag(CN)₂] calculated in part (a) to find the mass of Zn(CN)2 produced.