A colloid is formed by adding FeCl3 in excess of hot water. What will happen if excess sodium chloride is added to this colloid?
FeCl3 when added into hot water, it forms hydrated ferric oxide, which is a positively charged sol due to absorption of Fe3+ ions. In NaCl, there are negatively charged chloride ions which coagulate the positively charged hydrated ferric oxide. This results the coagulation of sol.