Match List-I with List-II
| List-I | List-II |
| (Constants) | (Used directly in the expressions of) |
| (A) Ebullioscopic constant | (I) Depression in freezing point. |
| (B) Henry’s Law constant | (II) Osmotic pressure. |
| (C) Cryoscopic constant | (III) Elevation in boiling point. |
| (D) Gas constant | (IV) The solubility of gas |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A) - (III), (B) - (IV), (C) - (I), (D) - (II)
Each constant in the list appears directly in one standard relationship for solutions:
(A) Ebullioscopic constant — This matches (III) Elevation in boiling point. \( \displaystyle \Delta T_b=K_b\,m \)
Kb (the molal elevation constant) is the elevation of boiling point for a 1 molal solution.
(B) Henry’s Law constant — This matches (IV) The solubility of gas. \( \displaystyle p=K_H\,x \)
Here x is the mole fraction of the gas in the solution, which is a measure of its solubility. The higher the KH of a gas, the lower its solubility.
(C) Cryoscopic constant — This matches (I) Depression in freezing point. \( \displaystyle \Delta T_f=K_f\,m \)
Kf (the molal depression constant) is the depression of freezing point for a 1 molal solution.
(D) Gas constant — This matches (II) Osmotic pressure. \( \displaystyle \pi=CRT \)
This is the van’t Hoff equation for osmotic pressure, where C is the molar concentration.
Shortcut: The pair (A)–(III) appears in Options (1) and (2), and (B)–(IV) then leaves only Option (2).