Final answer:
The equilibrium constant expression for the reaction Cu(s) + 2Ag+ (aq) → Cu2+ (aq) + 2Ag(s) is Kc = [Cu2+]/[Ag+]^2, omitting the solids from the expression.
Step-by-step explanation:
The concentration equilibrium constant expression, also known as the equilibrium constant, for the given reaction Cu(s) + 2Ag+ (aq) → Cu2+ (aq) + 2Ag(s), is written using the concentrations of the aqueous species only. Since solids do not appear in the expression, the correct equilibrium constant expression would be:
Kc = [Cu2+]1/[Ag+]2
To further explain, in a reaction quotient or equilibrium expression, we do not include the concentrations of pure solids or liquids. Therefore, in this case, the concentration of solid copper (Cu) and solid silver (Ag) would not be included in the expression. You only include the concentrations of the aqueous ions, which are Cu2+ and Ag+.