Question

Calculate the osmotic pressure of a solution containing $6.00g$ urea and $9.00g$ glucose in a one litre of solution at ${27}^{o}C$.

• A. $1.23atm$
• B. $3.69atm$
• C. $2atm$
• D. $4.64atm$

Answer 1

The correct option is B $3.69atm$

Both urea and glucose has 'i' factor value of 1.
Number of moles in $6g$ of urea,
$=\frac{6}{60}=\frac{1}{10}=0.1mol$

Number of moles in $9g$ of glucose,
$=\frac{9}{180}=\frac{1}{20}=0.05mol$

$\text{Total no. of moles}=0.1+0.05=0.15mol$

$\text{Volume of solution}=1L$

$\text{Concentration of solution},C=0.15mol/L$

$\text{Osmotic pressure,}\pi =CRT$

$\pi =0.15\times 0.082\times 300$

$\pi =3.69atm$