Calculating constant equilibrium

Question

how do you calculate the constant equilibrium if what's known is ONLY the initial concentration of cC and dD aka the products. 

 

Using the ice table how do you determine what the Keq if the initial concentration of the reactants is not given? 

Answer 1

Are you asking about the equilibrium constant, Keq? If so, it is simply products raised to their coefficients divided by reactants raised to their coefficients. For

aA + bB ==> cC + dD

Keq = [C]^c[D]^d/[A]^a[B]^b