Which one of the following statements is incorrect?
Correct answer: C. 0.1 M NaCl solution and 0.1 m sugar solution have the same boiling point
- A. A solution freezes at a lower temperature than the pure solvent
- B. A solution boils at a higher temperature than the pure solvent.
- C. 0.1 M NaCl solution and 0.1 m sugar solution have the same boiling point
- D. Osmosis cannot take place without a semi-permeable membrane.
Explanation
Molarity is the moles of solute in 1 litre of solution Molality is the moles of solute per 1 kg of solvent. Therefore, a molal solution is less concentrated than a molar solution because the latter contains less solvent. The answer is C as the elevation of the boiling point depends on the number of particles added to the solution. Since we have NaCl being ionic unlike sugar, NaCl ionizes to give Na ions and Cl ions, doubling the number of particles in the solution, leading to a further elevation in the boiling point.
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