Which one of the following pairs of solution can we expect to be isotonic at the same temperature

Options

A. 0.2 M urea and 0.2 M NaCl
B. 0.1 M urea and `0.2 M MgCl_(2)`
C. 0.1 M NaCl and `0.1 M Na_(2)SO_(4)`
D. `0.1 M Ca(NO_(3))_(2)` and `0.1 M Na_(2)SO_(4)`

Answer

D

Explanation

Carboxylic acids dimerises in benzene due to intermolecular hydrogen bonding.