Question

Hexachlorophene has been used in germicidal soap. What is its molar mass if 0.640 grams of the compound, dissolved in 25.0 grams of chloroform, produces a solution whose boiling point is 61.93��C? (The normal boiling point for chloroform is 61.70��C and its molar mass is 119.38 g/mol).

Answer 1

To determine the molar mass of the compound, we need to use the boiling point elevation equation.

Step-by-step explanation:

To determine the molar mass of the compound, we need to use the boiling point elevation equation:

Boiling point elevation = Kb * molality

where Kb is the molal boiling point elevation constant and molality is the amount of solute in moles divided by the mass of the solvent in kilograms.

In this case, the boiling point elevation is 61.93 - 61.70 = 0.23°C. The mass of chloroform is 25.0 g, and its molar mass is 119.38 g/mol. We can calculate the molality using the given mass of the compound and the molar mass.

molality = (0.640 g / molar mass) / (25.0 g / 1000)

Finally, we can rearrange the boiling point elevation equation to solve for the molar mass:

Molar mass = (Boiling point elevation / Kb) * (mass of solvent / molality)