Experiment 99

Objective

To prepare acetamide (ethanamide) by reacting ethanoic acid with ammonium carbonate.

Introduction

Ethanoic acid reacts with ammonium carbonate to form ammonium ethanoate. Upon heating, ammonium ethanoate decomposes to produce acetamide, a colorless compound.

Reaction:

1.    Formation of ammonium ethanoate:

(NH4​)2​CO3 ​+ CH3​COOH → CH3​COO(NH4​) + NH3​ + H2​CO3​​

2.    Formation of acetamide:

CH3​COO(NH4​) → CH3​CONH2 ​+ H2​O

Materials

Chemicals

·       Ethanoic acid (acetic acid)

·       Ammonium carbonate

Apparatus

·       Two test tubes

·       Two test tube holders

·       Dropper

Reagents

·       5–6 ml of ethanoic acid

·       Equivalent amount of ammonium carbonate

Procedure

1.    Place ethanoic acid and ammonium carbonate in a test tube.

2.    Secure the test tube in a holder.

3.    Heat the mixture for 1–2 minutes using a Bunsen burner.

4.    Stop heating once a colorless liquid of ammonium ethanoate is formed.

Observation

A colorless liquid is formed, indicating the presence of acetamide.

Questions

1.    What is an ester?

2.    How is an ester formed?

3.    What reagents are used for ester preparation?