A test to distinguish between ethanol and methanol

Several test tubes containing liquids that range in colour from light yellow, through orange to dark brown, representing the iodoform reaction.

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A class practical to distinguish between methanol and ethanol using the iodoform reaction. Includes kit list, safety instructions, procedure and teaching notes.

In this experiment students will reveal how methanol and ethanol behave differently when treated with iodine and sodium hydroxide solutions. Ethanol reacts to form a yellow solid, tri-iodo-methane, often called iodoform.

This experiment takes about 20 minutes. It is eminently suitable for students who have the iodoform reaction in their specification. For others, it is a good observational exercise and an extension for more able students.

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