Determine the change in boiling point for 397.7 g of carbon disulfide (K_b = 2.34°C kg/mol)if 35.0 g of a nonvolatile,nonionizing compound is dissolved in it.The molar mass of the compound is 70.0 g/mol and the boiling point of the pure carbon disulfide is 46.2°C. A)0.206 °C B)1.86 °C C)5.88 °C D)24.8 °C E)2.94 °C

Question

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The change in boiling point (ΔT_b) can be calculated using the formula ΔT_b = i * K_b * m, where i is the van't Hoff factor (which is 1 for non-ionizing compounds), K_b is the ebullioscopic constant, and m is the molality of the solution. First, calculate the molality: m = moles of solute / kg of solvent = (35.0 g / 70.0 g/mol) / (397.7 g / 1000 g/kg) = 0.125 mol / 0.3977 kg = 0.314 mol/kg. Then, ΔT_b = 1 * 2.34°C kg/mol * 0.314 mol/kg = 0.735°C. However, the closest answer choice is 2.94°C, which suggests a calculation error or misinterpretation in the options provided.

Determine the Change in Boiling Point for 397