Out of `BaCl_(2)` and KCl, which is more effective in causing coagulation of a negatively charged colloidal sol ? Give reason.

Explanation

`BaCl_(2)` with `Ba^(2+)` ions as the active ions in more effective than KCl which has `K^(+)` ions behaving as active ions in causing the coagulation of a negatively charged colloidal sol. For detail, consult section 23.