If molarity of the dilute solutions is doubled ,the value of molal depression constant`(K_(f))`will be:

Options

A. doubled
B. halved
C. tripled
D. unchanged

Answer

D

Explanation

For a dilute solution, the depression in freezing point `(Delta T_(f))` is directly proportional to molality (m) of the solution.
`Delta T_(f)prop m` or `Delta T_(f)=K_(f)m`
Where, `K_(f)` is called molal depression constant or freezing point depression only on nature of the solvent and independent ofcomposition of solute particles, i.e., does not depend on the concentration of solution.