Lesson 2 Lab: Weighing on an Analytical Balance & Distillation

PART 1

Begin by viewing the following Thinkwell video

15.1.8 CIA Demonstration: Weighing on an Analytical Balance

After you watch the above video, answer the questions below in sufficient detail:

(a) (2 pts) What are the features of an electronic balance? Include all of those discussed in the video.

Answer: There were two features of an electronic balance discussed in this video. First there is the electronic read out which makes the measurement very accurate and the tare feature which can reset the balance to zero when something such as a container is still on the balance (Yee, n.d., Weighing…).

(b) (1 pts) What does “tare” mean? What is the importance of the
I would attach a thermometer to the first cooking pot. Then there would be a coffee cup for the collection cup which would be connected to the pan using the plastic or copper pipe. The cooking pot would be placed at a higher level so the tubing could be placed downward. These are all items I have at home that could be used to make a homemade distillation apparatus.

(d) (1 pts) What is the difference between fractional and simple distillation? What is meant by “theoretical plates”?

Answer: Simple distillation is a method for separating a liquid from a solid or from another liquid, provided the boiling points of the two liquids are sufficiently separated; whereas fractional distillation is a method for separating two liquids with similar boiling points through use of repeated cycles of boiling and condensing (Yee, n.d., Distillation). Theoretical plates is the surface area available to a liquid in which to condense during distillation, the higher the theoretical plates the better separation allowed (Yee, n.d., Distillation).

(e) (1 pts) What is meant by “bumping”? What is meant by “reflux”?

Answer: Bumping is the eruption of a liquid due to superheating and reflux is the gentle boiling during distillation such that the vapors may continuously condense and boil to maintain the phase equilibrium (Yee, n.d., Distillation).

(f) (3 pts) Suppose you performed a distillation of a solution containing