where K is the equilibrium constant, and [A], [B], [C], and [D] are the concentrations of reactants and products.
K = [C]^c [D]^d / [A]^a [B]^b
Le Chatelier's principle states that when a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the equilibrium will shift in a direction that tends to counteract the effect of the change. petrucci genel kimya 2 pdf