CHM 112 Simple Distillation Lab

What is the mole percent of water in the solution that you are distilling? Remember, the solution in the distillation flask is 4 moles of water and 1 mole of glycerol. Hint: Mole percent is defined as the moles of a compound divided by the total moles of all compounds in the solution 100%. If you need a calculator you can access it at the top right of the LabPad. a) 90 mole percent water b) 20 mole percent water c) 80 mole percent water d) 40 mole percent water

80 mole Percent water

If your mixture has 3 males of methanol and 2 moles of water, what is the mole percent of methanol in the solution? a) 60 mole percent methanol b) 40 mole percent methanol c) 70 mole percent methanol d) 30 mole percent methano

A) 60 mole percent

When you collected 50 mL of distillate in the collection flask, the mole percent of water in the distillation flask decreased to approximately 20 mole percent . With your simple distillation set -up, what percentage of water will be in the vapor phase at this composition of the liquid ? Read the theory page if you don't remember how to interpret the boiling point composition curve . a) 72 mole percent water b) 98 mole percent water c) 92 mole percent water d) 86 mole percent water

B) 98 mole percent water

Cool on water should flow through the

Bottom (right) hose

How does it differ from the glycerol-water temperature vs volume plot that you observed during your first experiment ? a) The boiling points of the two compounds are more clearly defined. b) The transition between the two boiling points is more clearly defined . C)The boiling points of the two compounds are not as transparent and there is no defined transition between the two points . d) There is no difference between the two plots .

C)The boiling points of the two compounds are not as transparent and there is no defined transition between the two points .

At what temperature do you expect the 60 mole percent methanol in water mixture to boil? a ) 77 deg * C b ) 65 deg * C C) 81 deg * C d ) 72 deg * C

D

How far should you insert the thermometer into the distillation head? a) A thermometer is not necessary for a simple distillation. b) The thermometer bulb should extend down into the liquid in the distillation flask c) The thermometer bulb should be above the side arm connecting the condenser to the distillation head. d) The thermometer bulb should extend just below the side arm connecting the condenser to the distillation head .

D

The boiling point of methanol is 65 deg * C and the boiling point of water is 100 deg * C you think these compounds can be efficiently separated by simple distillation ) Yes No

Yes

Would boiling point decrease at higher elevation

Yesyou are at a higher elevation, the atmospheric pressure decreasesA lower atmospheric pressure means that the boiling point will decrease because a compound boils when its vapor pressure equals the atmospheric pressure .

Looking at the boiling point composition curve, at what temperature do you think your solution will start to boil? Remember , your solution is 80 mole percent water. If you do not know how to interpret a boiling point composition curve , read the theory section. a ) 110 deg * C b) 130 deg * C ) 120 deg * C d) 100 deg * C

a ) 110 deg * C

you collected the first drop from the distillation, what would be the mole percent methanol in that drop? Remember, your original distillation flask contains 60 mole percent methanol a) 83 mole percent methanol b) 100 mole percent methanol c) 73 mole percent methanol d) 93 mole percent methanol

a) 83 mole percent methanol

You collected the first drop from the glycerol-water distillation in a collection flask. Look at the boiling point composition curve. What mole percent water should be in the first drop collected? a) 70 mole percent water b) 100 mole percent water c) 80 mole percent water d) 90 mole percent water

b.) 100 mole percent

If the mole percent of methanol in the liquid phase in the distillation flask drops to 30%, what would be the mole percent of methanol collected in the collection flask? a) 57 mole percent methanol b) 77 mole percent methanol c) 67 mole percent methanol d) 47 mole percent methanol

c) 67 mole percent methanol

Interact with the LabPad to answer que THEORY MEDIA MISSION HOME When you collect distilate in the collection flask, what happens to the original mole percent of water in the distillation flask? a) The mole percent of water increases b) The mole percent of water remains the same c) The mole percent of water decreases d) You cannot determine what is happening to the mole percent of water

c) The mole percent of water decreases