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What is the property of boiling point elevation, and what equation is used to determine its effect?

User Chee
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Final answer:

Boiling point elevation is when a solution's boiling point is higher than the pure solvent's boiling point, caused by the presence of a solute lowering the solution's vapor pressure. The formula used to calculate this elevation is ΔTb = iKbm. This colligative property is affected by the number of particles rather than the type of solute.

Step-by-step explanation:

Boiling point elevation is the phenomenon where the boiling point of a solution is higher than that of the pure solvent. This occurs because the addition of a solute decreases the vapor pressure of the solution, requiring a higher temperature to reach the boiling point. A commonly used equation to calculate boiling point elevation is ΔTb = iKbm, where ΔTb is the increase in boiling point, i is the van 't Hoff factor which represents the number of particles the solute breaks into, Kb is the molal boiling-point elevation constant of the solvent, and m is the molality of the solution.

For instance, at 1.0 atm, the boiling point of water is 100°C. If a solute such as salt is added, forming a 2% saltwater solution, the water's boiling point might rise to approximately 102°C, resulting in a boiling point elevation of 2°C. Boiling point elevation is a colligative property, meaning it depends on the number of solute particles rather than their specific identity. Therefore, a 0.20 m solution of table salt and a 0.20 m solution of hydrochloric acid would produce the same boiling point elevation.

User Brownmike
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