Video: The chromate-dichromate equilibrium II

Video: The chromate-dichromate equilibrium II

Barium chromate is insoluble while barium dichromate is soluble. Addition of hydroxide ion to dichromate ion solution increases the chromate ion concentration above the solubility product of barium chromate:

Cr₂O₇^2-(aq) + 2 OH^-(aq) ® 2 CrO₄^2-(aq) + H₂O(l)
Ba²⁺(aq) + CrO₄^2-(aq) ® BaCrO₄(s)