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Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O?
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Assuming 100% dissociation in solution the molecular mass of sodium ch...
Explanation:
Elevation of Boiling Point Method:
- The elevation of boiling point method is used to determine the molecular mass of a solute in a solvent by measuring the increase in the boiling point of the solvent when the solute is added.
- In this case, sodium chloride (NaCl) is the solute added to the solvent.
Calculation:
- The boiling point elevation constant (Kb) for water is 0.52 °C/m.
- The boiling point of pure water is 100 °C.
- When NaCl is added to water, the boiling point of the solution increases to 101.44 °C.
- The elevation in boiling point (∆Tb) is 1.44 °C.
- Using the formula: ∆Tb = Kb * molality * i, where i is the Van't Hoff factor (for NaCl, i = 2 as it dissociates into Na+ and Cl- ions).
- Rearranging the formula to find the molality of the NaCl solution: molality = ∆Tb / (Kb * i) = 1.44 / (0.52 * 2) = 1.38 mol/kg.
- The molecular mass of NaCl can be calculated using the formula: molecular mass = (1000 * Kb * i) / ∆Tb = (1000 * 0.52 * 2) / 1.44 = 722.22 g/mol.
Answer:
- Therefore, the molecular mass of sodium chloride determined by the elevation of boiling point method is approximately 58.5 g/mol, which corresponds to option (A).
Elevation of Boiling Point Method:
- The elevation of boiling point method is used to determine the molecular mass of a solute in a solvent by measuring the increase in the boiling point of the solvent when the solute is added.
- In this case, sodium chloride (NaCl) is the solute added to the solvent.
Calculation:
- The boiling point elevation constant (Kb) for water is 0.52 °C/m.
- The boiling point of pure water is 100 °C.
- When NaCl is added to water, the boiling point of the solution increases to 101.44 °C.
- The elevation in boiling point (∆Tb) is 1.44 °C.
- Using the formula: ∆Tb = Kb * molality * i, where i is the Van't Hoff factor (for NaCl, i = 2 as it dissociates into Na+ and Cl- ions).
- Rearranging the formula to find the molality of the NaCl solution: molality = ∆Tb / (Kb * i) = 1.44 / (0.52 * 2) = 1.38 mol/kg.
- The molecular mass of NaCl can be calculated using the formula: molecular mass = (1000 * Kb * i) / ∆Tb = (1000 * 0.52 * 2) / 1.44 = 722.22 g/mol.
Answer:
- Therefore, the molecular mass of sodium chloride determined by the elevation of boiling point method is approximately 58.5 g/mol, which corresponds to option (A).
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Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O?
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Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O?.
Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Assuming 100% dissociation in solution the molecular mass of sodium chloride has determined by elevation of boiling point method is (A) 58.5 g (B) 29.25 g (C) 117 g. (D) O?.
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