Question

THE MOLAR MASS OF A VOLATILE LIQUID 1. A foil-covered flask was found to have a mass of 161.38 have a mass of 167.38 g. A volatile liquid was placed L00.0°C at a barometric pressure of 743.8 mm Hg. The foil-covered inside and heated to 100.0°C at a barometric press flask containing the vapor had a mass the molar mass of this volatile liquid. 's the vapor had a mass of 167.71 g and a volume of 147.0 mL. Calculate 2. One of the substances you will use is isopropanol with the molecular formula C3H80. Calculate its molar mass. 3. How would each of the following procedural errors affect the results (higher or lower value) to be expected in this experiment? Give your reasoning in each case (answers without reasoning will not be graded). a. All of the liquid was not vaporized when the flask was removed from the water bath. b. The flask was not dried before the final weighing with the condense inside. CONTINUED

Answer 1

Mass of volithe compound = 167.71g-167.38g = 0.33g P = 743. 8mmug = 0.978 atm 760 R = 0.0821 Lam prolk Ve 147.0 mL = 0.147L T= 100°c = 900 + 273=3732 leing PV = nRT 0.978801147=n 0.0821 x 373 n = 4.69x10 moles 0.33 4.69 xlors MM MM = 0.33 70.29 g/mol 4.69xlors