Organic Chemistry Laboratory Questions

REPUBLIC OF CAMEROON REPUBLIQUE DU CAMEROUN

Peace-Work-Fatherland Paix-Travail-Patrie

THE UNIVERSITY OF BAMENDA UNIVERSITE DE BAMENDA

P.O. Box 39 Bambili

Faculty of Science Department of Chemistry Lecturer: AWANTU/BANKEU and NOUDOU

Course Code: CHMS3101 Course Title: Organic Chemistry Laboratory

Date: 03/05/2017

hall: PBB07 time: 10:00-14:00 (3 hours)

Exercise 1 (9 marks)

Hard soap is one of the most available form of soap in Cameroon. Almost all the household in our country rely on it.

a) - Give the list of chemicals involved in the production of hard soap. 2marks

b) - Give the principle of the saponification reaction (R= -C

15

H

32

). 1mark

c) - Briefly describe the procedure use in this process 4marks

d) -Knowing that 500 g of sodium hydroxide was used to produce 3.235 kg of hard soap, determine the

percentage yield of the reaction. 2marks

Exercise 2(8 Marks)

The production of powder soap is an old and a well-known process. In Cameroon, it is locally produced by people

who don’t care much about the safety conditions usually followed in the laboratory.

a)- What are the risks to which we are exposed while producing the powder soap? 1mark

b)- Which chemicals are the most dangerous during this process? 1mark

c)- What shall we do to avoid any risk during this experiment? 2marks

d)- Give the procedure use in the production of powder soap. 4marks

Exercise 3 (18 Marks)

Aspirin is one of the oldest and one of the most consumed drugs that was patented in 1893 by Bayer. Aspirin as

many other drug has some biological properties as well as some side effects.

a)- What are the biological properties of aspirin? 0.5x3mark

b)- What are its side effects? 0.5x2marks

c)- Give the principle of synthesis of aspirin. 1.5mark

d)- What are the functional groups found in its structure? 1mark

e)- What is the catalyst used for this synthesis? 0.5mark

f)- What are systematic names of the reactants? Also indicate that of the by-product 1.5mark

g)- What is the solvent used during this synthesis? 0.5mark

h)- There are two main ways of purifying the synthesized aspirin. List them and specify which of them is the most

efficient and less time consuming. 0.5 X 2marks

i)- In the absence of spectroscopic data, which datum can we use to verify its purity? Is it reliable? 0.5mark

j)- Give a chemical test which can be used to ensure that the reaction leading to the synthesis of aspirin is complete.

0.5mark

k- Briefly describe procedure of the synthesis of this product. 3.5marks

l- Briefly describe procedure of purification of this product that you used in the laboratory. 3marks

m)- Determine the percentage yield of the reaction in a situation where 5 g of salicylic acid was used to produce

3.65 g of pure aspirin. 2 marks