Step1 Let M be molar mass of solute ; Moles of solute =1.2463/M
Step2 ΔTf= 4.9 ; Kf= 9.8 C/m
Step3 Molality of solute =(1.2463/M)(1000/10.9303)
Step4 ΔTf = Kf xMolality ; 9.8x1.2463x1000/Mx 10.9303 =4.9
Step5 M= 228.04
The freezing point of a solution of 1.104 g of an unknown nonelectrolyte dissolved in 36.81 g of benzene is 1.08°C. Pure benzene freezes at 5.48°C and its Kf value is 5.12°C/m. What is the molecular weight of the compound?
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26. The freezing point depression of a solution of 1.45g sample of an unknown nonelectrolyte dissolved in 25.00 mL of benzene(density d=0.879 g/mL) is 1.28°C. Pure benzene has Kf value of 5.12°C/m. What is the molecular weight of the compound? (10 points)
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0.230 g of a compound is dissolved in 10 g of cyclohexane. the solution freezes at 5.12 degrees celcius. calculate the molecular weight of the compound. the freezing point of pure benzene is 5.455 degrees Celsius and the kf = 5.065 degrees Celsius/ m
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A nonvolatile, non-dissociating solute was dissolved in 12.0 g of benzene (C6H6). The freezing point of the solution was measured as 1.3 °C, while pure benzene freezes at 5.5 °C. If pure benzene has a vapor pressure of 75 torr, what is the vapor pressure of this solution. For benzene, Kf = 5.12 °C/m and Kb = 2.53 °C/m.
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