Consider the two solutions:
I: `0.5 M NaCl` aqueous solution at `25^(@)C`,
`NaCl` is complete ionized.
II:`2.0 M C_(6)H_(5)COOH` in benzene at `25^(@)C`,
`C_(6)H_(5)COOH` dimerizes to the full extent.
Which of the following statements(s) is (are) correct?

Options

A. Both the solutions display equal osmotic pressure.
B. Both have equal vapour pressure.
C. Solution II is hypertonic.
D. Solution II has greater depression in freezing point than solution I.

Answer

A, D

Explanation

`NaCl`:0.5 M (i=2) `rArr C_(eff) =0.5 xx 2 =1 M`
`C_(6)H_(5)COOH:2.0 M (i=1/2) rArr C_(eff) = 2 xx 1/2=1 M`
`pi=C_(eff) RT rArr pi` is same as `C_(eff)` is same.
Since both the solutions have different solvents, vapour pressure will be different.
Solutions are isotonic.
`DeltaT_(f) = iK_(f).m rArr DeltaT_(f)` for solution II will be more as `(K_(f))_( "benzene") gt (K_(f))_( "water")`