Question

At constant temperature, the osmotic pressure of a solution is:
(A) Directly proportional to the square of the concentration
(B) Directly proportional to the square root of the concentration
(C) Directly proportional to the concentration
(D) Inversely proportional to the concentration

Answer 1

Hint: The minimum pressure which is required to be applied to the solution to prevent the inward flow of the solvent across a semipermeable membrane is known as osmotic pressure. This process is known as osmosis. If there is no osmotic pressure, there will be no movement of solvent. It is a unidirectional process. It tends to make the concentration of solute across the two sides of the membrane equal.

Complete Step by Step Answer:
The osmotic pressure is represented by pi ($\pi $). The factors on which osmotic pressure depends are the temperature and the concentration of solute. The formula for osmotic pressure is:
$\pi =icRT$; where $i$= van’t hoff index
$c$= Concentration of solute
$R$= Gas constant
$T$= Temperature (Kelvin)

From the formula, we can observe that the osmotic pressure of a solution is directly proportional to its concentration.
Correct Option: (C) Directly proportional to the concentration.

Additional Information: Osmotic pressure is a colligative property. The direction of flow of solvent is from that side of the semi-permeable membrane where the concentration of solute is low to the side where concentration of solute is high.

Note: The process of osmosis is important for the human body. In the human body, osmosis occurs in the small and large intestines. It plays an important role in the gastro-intestinal system and kidneys. It helps in getting all the essential nutrients from our food and also removes the waste products from the blood.