Reflux Method

Question 1

Name the five pieces of glassware

Answer 1

1. Round bottomed flask and pear shaped flask
2. Receiver
3. Screw-tap adptor (for thermometer usually)
4. Condensor (liebig)
5. Still head

Question 2

Describe the differences in the setup between a distillation and a reflux

Answer 2

A reflux uses an upright condensor while the distillation uses a horizontal condensor.

Question 3

Why do we need to use anti-bumbing granules in a reflux?

Answer 3

Stops the reaction boiling too aggresivley and ‘jumping’ or boiling over.

Question 4

Why do we leave the top of the condensor unstoppered?

Answer 4

This stops the pressure building up and reduces the risk of the apparatus exploding.

Question 5

Describe how the condensor allows the solution to be boiled for a long time.

Answer 5

The solution boils, turns into a gas and condenses in the condensor before falling back down into the reaction vessel. The mixture cannot escape.

Question 6

How far up should the vapor reach in the condensor?

Answer 6

No more than halfway up

Question 7

How should you heat a volatile liquid with a boiling point below 100oC?

Answer 7

With a water bath