Answer
a) The equilibrium constant is equal to the forward rate constant divided by the reverse rate constant.
b) No, the rate expressions for forward and reverse reactions cannot be written from the balanced chemical equation.
c) Yes, the equilibrium constant expression can be derived from the balanced chemical reaction.
Work Step by Step
a) In the reaction:
$aA+bB \longleftrightarrow cC+dD$, where a,b,c and d are constants,
equilibrium constant of concentration at constant temperature,
$K_{c} = \frac{k_{f}}{k_{r}} = \frac{[C]^{c}[D]^{d}}{[A]^{a}[B]^{b}}$
At equilibrium, rate of forward and backward reactions are equal.
b) Unless the reaction only involves one single step, the balanced chemical equation is not enough to write the rate expressions.
c) The equilibrium constant expression depends only upon the reactants and products, and not on any reaction intermediate.
