Question

A solution is prepared by dissolving $0.6g$ of urea (molar mass = $60gmo{l}^{-1}$) and $1.8g$ of glucose (molar mass = $180gmo{l}^{-1}$) in $100mL$ of water at ${27}^{0}C$. The osmotic pressure of the solution is :
$(R=0.08206Latm{K}^{-1}mo{l}^{-1})$

• A. $4.92atm$
• B. $1.64atm$
• C. $2.46atm$
• D. $8.2atm$

Answer 1

The correct option is A $4.92atm$

For mixed solutes in the solution, osmotic pressure;

$\Pi =\frac{n_1+n_2}{V}\times RT=\frac{(\frac{0.6}{60}+\frac{1.8}{180})}{0.1}\times 0.08206\times 300$

$\Pi =4.9236atm$