If the concentration of product C at equilibrium  was measured to be 0.456 what are the initial conditions?

The initial concentrations were given to you. You are asked to find the equilibrium concentrations of everything. You can do this by determining how much C was consumed and then using the stoichiometry of the balanced equation to calculate the other concentrations:

molarity of C consumed = 0.651 - 0.456 = 0.195 M

0.195 M C X (1 M D / 3 M C) = 0.065 M D consumed. So,
equilibrium [D] = 0.754 - 0.065 = 0.689

0.195 M C X (2 M A / 3 M C) = 0.130 M = [A]

0.195 M C X (1 M Y / 3 M C) = 0.065 M = [Y]

K = [C]^3 [D]/[A]^2[Y]
K = (0.456)^3 (0.689) / (0.130)^2 (0.065) = 59.5...Show more