Final answer:
To calculate the molar mass of the compound, we need to use the formula for boiling point elevation and solve for the molar mass. Given the change in boiling point, the mass of the solute, and the mass of the solvent, we can substitute these values into the formula and solve for the molar mass. In this case, the molar mass of the compound is calculated to be 78.0 g/mol.
Step-by-step explanation:
In order to calculate the molar mass of the compound, we can use the formula:
ΔT = Kb * m * i
where ΔT is the change in boiling point, Kb is the ebullioscopic constant for the solvent, m is the molality of the solution, and i is the van't Hoff factor which is 1 for a nonelectrolyte.
In this case, we know that the change in boiling point (ΔT) is 64.5 °C - CHCl3 (bp 61.2 °C) = 3.3 °C. The molality (m) can be calculated by dividing the moles of solute by the mass of the solvent in kg.
m = (35.7 g / molar mass) / (220.0 g / 1000)
Substituting the values into the formula, we have:
3.3 °C = Kb * [ (35.7 g / molar mass) / (220.0 g / 1000) ] * 1
Simplifying the equation and solving for the molar mass:
Molar mass = (35.7 g / (3.3 °C * Kb * [ (220.0 g / 1000) ]
Based on the given options, the molar mass of this compound would be 78.0 g/mol (option A).