Final answer:
The correct expression for the equilibrium constant Kc for the reaction includes only the concentrations of aqueous ions and the partial pressures of gases, resulting in Kc = [H₃O+]^2 / ([Sn^2+] * [O₂]^(0.5)). Solids and liquids are not included in the expression.
Step-by-step explanation:
The correct expression for the equilibrium constant Kc for the given reaction (Sn2+ (aq) + ½ O₂(g) + 3 H₂O(l) ⇌ SnO₂(s) + 2 H₃O+ (aq)) does not include solid (s) or liquid (l) phases because they are pure substances and their activity is regarded as constant and is thus incorporated into the equilibrium constant.
Also, the equilibrium constant is based on the concentrations of aqueous solutions and partial pressures of gases in a balanced chemical equation, with products in the numerator and reactants in the denominator, each raised to the power of their stoichiometric coefficients in the balanced equation.
To form the correct expression for Kc, we only include the aqueous and gas species, which in this case are [Sn2+ (aq)] and [O₂(g)] to the power of 0.5 in the denominator, and [H₃O+ (aq)] squared in the numerator, as per the stoichiometry of the reaction. Therefore, none of the listed options are correct.
The correct expression for the given reaction is:
Kc = [H₃O+]^2 / ([Sn2+] * [O₂]^(0.5))