updated last Tuesday, November 08, 2005


Week 7 Problem Set 30 BL (Esterification Reaction)


Useful Link: Refractometer

ATTN: answers to the below questions are due at the start of your lab period; these answers should be part of your pre-lab write-up.


1. Reaction planning of esterification carried out in the lab

a. Which container is used for the reaction? Which one is used for the work-up?

b. Which reactant is used in excess here? Why?

c. What is the function of the concentrated sulfuric acid in this reaction?

d. Why is the reaction mixture refluxed? Which setup is used here?

e. Why is the product distill in vacuo at the end? Which precaution have to be taken here?

f. Why is an extraction with sodium bicarbonate used during the work-up?

2. A student refluxes a mixture 1.35 g of m-methoxybenzoic acid, 1.00 mL of ethanol and 0.5 mL of concentrated sulfuric acid for two hours. After the work-up, the student isolated 1.50 of the ester.

a. Show a balanced chemical equation for the reaction.

b. Determine the yield of the reaction. Show all calculations.

c. The student observes refractive index of nD22.5= 1.5140. Which conclusion can he draw from this observation?

3. Extraction

a. Construct a flow diagram to separate m-methoxyphenol, benzoic acid and fullerene.

b. Construct a flow diagram to separate a 2-acetylnaphthalene, naphthalene and acetic acid.