How is the direction of a chemical reaction determined?

Answer 1

If K(equilibrium constant) is greater than Q(concentration constant at a prticular point) then the reaction will tend to the right. If Q is less that K the reverse reaction will occur and if they are equal the reaction is at equilibrium. Example: aA+bB<--->cC+dD K=1.5 if Q<1.5 the reaction is aA + bB ---> cC + dD if Q> 1.5 the reaction is aA + bB <--- cC + dD K= [C]c[D]d/ [A]a[B]b at any point Q=[C]c[D]d/ [A]a[B]b at a particular point in time

Answer 2

The direction of a chemical reaction is determined by the free energy change (ΔG) of the reaction. If ΔG is negative, the reaction is spontaneous in the forward direction; if ΔG is positive, the reaction is non-spontaneous in the forward direction; and if ΔG is zero, the reaction is at equilibrium. This is determined by the difference in free energy between the products and reactants.