Question

The osmotic pressure of urea solution at ${10}^{o}C$ is $500$ mm. The osmotic pressure of the solution becomes $105.3$ mm when it is diluted and the temperature raised to ${25}^{o}C$. The extent dilution is:

• A. $8$ times
• B. $5$ times
• C. $4$ times
• D. $7$ times

Answer 1

The correct option is B $5$ times

Solution

At 10 degree Celsius the osmotic

pressure of area solution is

500 mm

The solution is diluted and the

temperature is rained to ${25}^{\circ }C$

$=\frac{P{i}_1}{P{i}_2}=\frac{t_1{v}_2}{t_2{v}_1}$

$=\frac{500}{105.3}=\frac{283\times v_2}{293\times v_1}$

$=\frac{500\times 293}{105.3\times 283}=\frac{v_2}{v_1}$

$=\frac{146500}{29799.9}=\frac{v_2}{v_1}$

$=4.91\cong 5$

i.e, $\frac{v_2}{v_1}=5$

Therefore, the Extent dilution is 5 times.