Match List-I with List-II
| List-I Osmotic pressure | List-II Properties |
| (A) van’t Hoff factor ‘i’ | (I) molar concentration of solution |
| (B) The osmotic pressure is directly proportional to | (II) dimensionless |
| (C) A hypertonic solution is one whose osmotic pressure is | (III) lower than the other solution |
| (D) A hypotonic solution is one whose osmotic pressure is | (IV) higher than the other solution |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
Osmotic pressure is the extra pressure that must be applied to a solution to stop solvent flowing into it through a semipermeable membrane. For a dilute solution it is given by the van’t Hoff equation, and two solutions are compared by their osmotic pressures:
\( \displaystyle \pi=i\,CRT \)
(A) van’t Hoff factor ‘i’ — This matches (II) dimensionless. It is a ratio of two numbers of particles (particles actually present after association or dissociation, divided by particles expected), so its units cancel.
\( \displaystyle i=\frac{\text{normal molar mass}}{\text{abnormal molar mass}} \)
(B) The osmotic pressure is directly proportional to — This matches (I) molar concentration of solution. At a fixed temperature, R and T are constant in π = CRT, so π rises in step with C (in mol L−1).
(C) A hypertonic solution is one whose osmotic pressure is — This matches (IV) higher than the other solution. A cell placed in a hypertonic solution (e.g. concentrated salt solution) loses water and shrinks.
(D) A hypotonic solution is one whose osmotic pressure is — This matches (III) lower than the other solution. A cell placed in a hypotonic solution (e.g. pure water) takes in water and swells.
Shortcut: The pair (A)–(II) appears only in Option (4).