Caryophyllene, a nonelectrolyte, is one of the compounds responsible for the flavor of cloves. A 207 mg sample of caryophyllene was dissolved in 1.00 g of chloroform (K_b = 3.63°C/m), increasing the boiling point of chloroform by 3.68°C. What is the molar mass of caryophyllene? A) 204 g/mol B) 156 g/mol C) 164 g/mol D) 193 g/mol E) 219 g/mol

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Quizplus · Accepted Answer

The boiling point elevation formula is ΔT = i * Kb * m. Since caryophyllene is a nonelectrolyte, i = 1. Rearranging the formula to find molality (m), we get m = ΔT / Kb = 3.68°C / 3.63°C/m = 1.0138 m. Molality is moles of solute per kg of solvent, so moles of caryophyllene = 1.0138 m * 0.001 kg = 0.0010138 mol. The molar mass is mass/moles = 0.207 g / 0.0010138 mol = 204 g/mol.

Caryophyllene, a Nonelectrolyte, Is One of the Compounds Responsible for the Flavor