Question

Identify the colligative property from the followings?

• A. Vapour pressure of solution.
• B. Osmotic pressure of solution.
• C. Boiling point of solution.
• D. Freezing point of solution.

Hint:

Osmotic pressure is itself a colligative property; the others change as lowering, elevation or depression.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
Colligative properties depend only on the number of solute particles dissolved, not on their nature. The four standard colligative properties are relative lowering of vapour pressure, elevation of boiling point, depression of freezing point and osmotic pressure.

Step 2: Why osmotic pressure fits
Osmotic pressure is given by \(\pi=CRT\). It depends on the concentration of particles and the temperature, and not on what the solute is. It is a colligative property in its own right.

Step 3: The other options
Vapour pressure of a solution, its boiling point and its freezing point are properties of the solution that change when solute is added. The colligative quantities are the relative lowering of vapour pressure, the elevation of boiling point and the depression of freezing point, which are changes caused by the solute.

Step 4: Conclusion
Among the options as stated, osmotic pressure is the colligative property, option (B).

Final Answer:
Osmotic pressure depends only on the number of dissolved particles, option (B). \[ \boxed{\text{Osmotic pressure}} \]