Question

Two solutions of $KNO_{3}$ and $CH_{3}COOH$ are prepared separately. Molarity of both is 0.1 M and osmotic pressures are $P_{1}$ and $P_{2}$ respectively. The correct relationship between the osmotic pressures is:

• A. $P_{2} >\,P_{1}$
• B. $P_{1}= P_{2}$
• C. $P_{1} >\,P_{2}$
• D. $\frac{P_{1}}{P_{1}+P_{2}}=\frac{P_{2}}{P_{1}+P_{2}}$

Answer 1

Answer: (C)

$KNO_{3}$ is is 100% ionised while $CH_{3}COOH$ is weak electrolyte
$\therefore i_{KNO_3} >i_{CH_3 COOH} $
$\therefore P_{1} >\,P_{2}$