To determine the equilibrium constant Kc for the reaction, we need to know the equilibrium concentrations of all species involved. However, we are only given the initial concentrations of Ag+ and NH3. To find the equilibrium concentrations, we can set up an ICE Initial, Change, Equilibrium table and use the stoichiometry of the balanced equation.Initial concentrations:[Ag+] = 0.005 M[NH3] = 0.025 M[Ag NH3 2+] = 0 M since the complex has not yet formed Change in concentrations:Let x be the change in concentration for Ag+ and Ag NH3 2+.Since the stoichiometry of NH3 is 2:1 with respect to Ag+, the change in concentration for NH3 will be 2x.Equilibrium concentrations:[Ag+] = 0.005 - x[NH3] = 0.025 - 2x[Ag NH3 2+] = xNow we can write the expression for the equilibrium constant Kc :Kc = [Ag NH3 2+] / [Ag+][NH3]^2 We need to find the value of x to determine the equilibrium concentrations and calculate Kc. To do this, we can use the solubility product constant Ksp for silver ion Ag+ . The Ksp for silver ion is 1.77 x 10^-10.Ksp = [Ag+][NH3]^2Substitute the equilibrium concentrations into the Ksp expression:1.77 x 10^-10 = 0.005 - x 0.025 - 2x ^2This is a cubic equation, which can be difficult to solve analytically. However, we can make an assumption that x is very small compared to the initial concentrations, so we can approximate:1.77 x 10^-10 0.005 0.025 - 2x ^2Now, we can solve for x:1.77 x 10^-10 0.005 0.025 ^2x 5.64 x 10^-7Now that we have the value of x, we can find the equilibrium concentrations:[Ag+] 0.005 - 5.64 x 10^-7 0.005 M[NH3] 0.025 - 2 5.64 x 10^-7 0.025 M[Ag NH3 2+] 5.64 x 10^-7 MFinally, we can calculate the equilibrium constant Kc :Kc = [Ag NH3 2+] / [Ag+][NH3]^2 Kc = 5.64 x 10^-7 / 0.005 0.025 ^2 Kc 1.80 x 10^5The equilibrium constant for the reaction at 25C is approximately 1.80 x 10^5.