Question

Write the formula for coefficient Q ?

Answer 1

The main difference between K and Q is that K describes a reaction that is at equilibrium, whereas Q describes a reaction that is not at equilibrium. To determine Q , the concentrations of the reactants and products must be known. For a given general chemical equation:

aA+bB⇌cC+dD(1)

the Q equation is written by multiplying the activities (which are approximated by concentrations) for the species of the products and dividing by the activities of the reactants. If any component in the reaction has a coefficient, indicated above with lower case letters, the concentration is raised to the power of the coefficient. Q for the above equation is therefore:

Qc=[C]c[D]d[A]a[B]b(2)

hope it help