A solution is prepared by dissolving 7.00 g of glycerin (C₃H₈O₃)in 201 g of ethanol (C₂H₅OH).The freezing point of the solution is ________°C.The freezing point of pure ethanol is -114.6°C at 1 atm.The molal-freezing-point-depression constant (K_f)for ethanol is 1.99°C/m.The molar masses of glycerin and of ethanol are 92.1 g/mol and 46.1 g/mol,respectively. A) -121.3 B) 0.752 C) -107.9 D) -113.8 E) -115.4

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The freezing point depression ($\Delta T_f$) is calculated using the formula $\Delta T_f = i \cdot K_f \cdot m$, where $i$ is the van't Hoff factor (which is 1 for glycerin, a non-electrolyte), $K_f$ is the molal freezing point depression constant for the solvent (1.99°C/m for ethanol), and $m$ is the molality of the solution. First, calculate the moles of glycerin ($\frac{7.00 \, \text{g}}{92.1 \, \text{g/mol}}$), then calculate the molality ($\frac{\text{moles of solute}}{\text{kg of solvent}}$). Finally, use the $\Delta T_f$ formula to find the change in freezing point and subtract this from the pure solvent's freezing point (-114.6°C) to find the solution's freezing point.

A Solution Is Prepared by Dissolving 7