The following are some statements about active masses.

 (A) Active masses of pure liquids and solids are taken as unity.

 (B) Active mass of electrolytes is taken as

morality.

 (C) For dilute solutions of non-electrolytes, the active mass can be taken as molarity. The correct combination is.

Solvent (excess) is seen as having the same active mass as pure liquids and solids, which are both fixed quantities (one). because the number or volume of the vessel has no effect on the activity. Also, dilute solution is non- electrolyte.

Therefore, the correct answer is option (C) A and C.