Question

In the following cases, the number of solutions which have identical equilibrium molarity and analytical molarity are :
(a) $1$ M glucose solution
(b) $1$ M $H_{3}P{O}_4$ solution
(c) saturated $AgI$ solution
(d) solution of $LiCl$ in ether

Answer 1

When the given compound behaves as a non electrolyte, it will dissolve in the solution without dissociation.
In such a case, the equilibrium molarity will be equal to the analytical molarity.

When the given compound behaves as an electrolyte, it dissociates into solution in constituent ions.

In such cases, the equilibrium molarity and the analytical molarity are different.

(a) Glucose is a non-electrolyte. In solution, it does not dissociate into ions.

(b) Phosphoric acid is an electrolyte. In solution, it dissociates according to the equation $H_{3}P{O}_4\leftrightarrow H^{+}+{H_{2}P{O}_4}^{-}$.

(c) Silver iodide is insoluble in water. Hence there is no dissociation of silver iodide.

(d) $LiCl$ behaves like a non-electrolyte in ether. There is no dissociation of lithium chloride in ether.

Hence, in (a), (c) and (d), analytical and equilibrium concentrations (molarity) are identical.