A solution containing `8.6 g` urea in `1 L` was found to be isotonic with `5%(weight//volume)` solution of an organic non-volatile solute. The molecular weight of latter is

Options

A. 348.9
B. 34.89
C. 3489
D. 861.2

Answer

A

Explanation

For two electrolyte solution if isotonic `C_(1) = C_(2)`
`W_(1)/(M_(1) V_(1)) = W_(2)/(M_(2) V_(2)):. 8.6/(60 xx 1000)=5/(M_(2) xx 100)`
`M_(2) = (5 xx 1000 xx 60)/(8.6 xx 100)=348.9`