Question

Questions about distillation:

Titration Data - Fractional Distillation -Simple Distillation - Temperature (Celsius) -- -- --- --- --- --- -- --- -- --- B.P. methanol = 65C B.P. ethanol = 78C 0 0 0 0 0 0 0 0 0 15 Volume (ml) 1. Why does the fractional distillation show no change in temperature while the system is heated and approximately 20mL is distilled? What is occurring when the temperature increases rapidly at about 25ml? 2. At 70°C, the vapour pressure of ethanol is 500 Torr. That of methanol is 800 Torr. At 70°C, would you expect the vapor to be a. Nearly 100% methanol b. Nearly 100% ethanol C. A mixture of similar amounts of ethanol and methanol Explain your thinking. 3. Based on question 2: why is it difficult to separate two liquids of similar boiling points using simple distillation? 4. What is the relative purity of each distillate at 14mL, comparing the simple and fractional distillate (points circled in red)?

Answer 1