# To coagulate gelatin sol, which of the following is most effective :—  (1) NaCl                 (2) $N{A}_{3}P{O}_{4}$ (3) $AlC{l}_{3}$             (4) Alcohol

Dear student,
For coagulation of gelatin, one must remove the water layer developed on the sol and for that we need a dehydrating agent. Now Na3PO4 is a good dehydrating agent and hence can best be used to remove water layer which will coagulate the gelatin sol.

Hope it helps
Regards

• -24
What are you looking for?