Classification Of Colloids

Step 1: Understanding the Concept: Arsenious sulphide (As S ) is a negatively charged colloid. Coagulating power follows Hardy-Schulze rule: higher valence of oppositely charged ion has greater coagulating power.

Step 2: Detailed Explanation: As S is negative, so cations cause coagulation. Coagulating power is proportional to charge on the cation. Hence, the order is:

Step 3: Final Answer: