Problem: A student weighs out 1.556 g of t-butyl alcohol into a large test tube and measures the freezing point of the pure solvent to be 21.4°C, Next the student weighs out 1.056 g of water and adds it to the test tube with the t-butyl alcohol and measures the freezing point of the mixture to be 14.8°C. The Kf is calculated to be 0.17 °C kg/mol. What is the molar mass of the unknown in grams? Show all your work.

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A student weighs out 1.556 g of t-butyl alcohol into a large test tube and measures the freezing point of the pure solvent to be 21.4°C, Next the student weighs out 1.056 g of water and adds it to the test tube with the t-butyl alcohol and measures the freezing point of the mixture to be 14.8°C. The Kf is calculated to be 0.17 °C kg/mol. 

What is the molar mass of the unknown in grams? Show all your work.

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