Experiment 19

Objective

To determine the presence of methanol by its reaction with salicylic acid, forming methyl salicylate in the presence of sulfuric acid.

Introduction

Methanol reacts with salicylic acid in the presence of sulfuric acid to produce methyl salicylate, commonly known for its characteristic odor, which serves as an indicator of methanol presence.

Reaction Overview

CH3OH + C7H6O3  →  C8 H 8O3 + H2O

(Methanol + Salicylic Acid → Methyl Salicylate + Water)

Material

Chemicals

·       Methanol (CH₃OH)

·       Salicylic acid

·       Sulfuric acid (H₂SO₄)

Apparatus

·       Test tube

·       Test tube holder

·       Bunsen burner

Reagents

·       Mix 2-3 mL of methanol with 5-6 mL of salicylic acid in the presence of sulfuric acid.

Procedure

1.    Preparation of Reaction Mixture

o   Place methanol and salicylic acid in a test tube.

2.    Addition of Sulfuric Acid

o   Add 1-2 drops of sulfuric acid to the test tube.

3.    Heating

o   Heat the test tube gently for a few minutes.

4.    Observation of Odor

o   Note the distinct wintergreen odor, indicating the formation of methyl salicylate.

Observation

The presence of a wintergreen odor confirms the production of methyl salicylate, indicating that methanol is present.

Questions

1.    What odor is produced during the methanol test?

2.    Why is salicylic acid used in the methanol test?