Equilibrium between octahedral and tetrahedral coordination complexes of Co2+ in solution is established with constant equilibrium K unless the temperature changes. When the concentrations of reactants and products are changed, the equilibrium position shifts to reduce any disturbance and reestablish the equilibrium. The color change of the mixture of CoCl2, methanol and 2-propanol depending on their concentration is an evidence the shift of equilibrium. By adding more methanol to the equilibrium mixtures causes dark blue 2-propanol solution turns into a lighter blue. As stated previously, equilibrium constant only changes with temperature changes. The mixture in the lower temperature has the lower Keq than higher temperature because the reaction
