Question

Osmotic pressure of urea solution at 10$^\circ$C is 500 mm. Osmotic pressure of the solution becomes 1053 mm when it is diluted and the temperature israised to 25 $^\circ$C. The extent of dilution is

• A. 6 times
• B. 5 times
• C. 7 times
• D. 4 time

Answer 1

Answer: (B)

5 times

Answer 2

$\frac{\pi_1}{\pi_2} = \frac{n_1 RT_1 /V_1}{n_2 RT_2 /V_2}$ or $\frac{500}{105.3} = \frac{283 /V_1}{298/V_2}$ $\therefore$ $V_2 /V_1$ = 5