Which of the following sets of solutions of urea
.

Options

A. 9. 1 `gL^(-1)` urea and 6.0 `gL^(-1)`sucrose
B. 3.0 `gL^(-1)` 1 urea and 3.0 `gL^(-1)` sucrose
C. 6.0 `gL^(-1)` urea and 9.0 `gL^(-1)` sucrose
D. 3.0 `gL^(-1)` urea and 17.1 `gL^(-1)` sucrose

Answer

D

Explanation

Formula for osmotic pressure, `pi = CRT`
Considering the set given in option (d), i.e., `3.0 gL^(-1)` urea and `17.1 gL^(-1)` sucorse.
Given molecular mass of urea `60 g mol^(-1)` and molecular mass of sucrose `342 g mol^(-1)` For urea.
Conc. `C = (3)/(60) = (1)/(20)`
Osmetic pressure `pi_(1) = (1)/(20) xx R xx T`
For sucrose conc. `C = (17.1)/(342) = (1)/(20)`
`:.` Osmotic pressure, `pi_(2) = (1)/(20) RT`
Thus set of solution of urea and sucrose given in option (d) is isotonic.