Out of BaCl2 and KCl, which one is more effective in causing coagulation of a negatively charged colloidal sol?

According to the Hardy-Schulze rule, greater the valency of a flocculating ion the greater is its power to cause precipitation. Between Ba2+ (from BaCl2) and K+ (from KCl), Ba2+ has greater valency. Therefore, BaCl2 will be more effective in causing the coagulation of a negatively charged colloidal sol.