A saturated solution of is present over its own solid precipitate. If additional ions are introduced — Ionic Equilibrium Chemistry Question
Question
A saturated solution of $Ag_2CrO_4$ is present over its own solid precipitate. If additional $CrO_4^{2-}$ ions are introduced into the solution (e.g., by adding $K_2CrO_4$), this action will predominantly result in:
💡 Solution & Explanation
Adding $CrO_4^{2-}$ ions increases the concentration of the anion in the $Ag_2CrO_4 \rightleftharpoons 2Ag^+ + CrO_4^{2-}$ equilibrium. According to Le Chatelier's principle (Common Ion Effect), the system will shift backward to consume the added $CrO_4^{2-}$, precipitating more solid $Ag_2CrO_4$ and thereby drastically decreasing the free $Ag^+$ concentration in the solution. $K_{sp}$ remains constant as long as temperature is constant.