What is the test to distinguish between ethanol and ethanoic acid?
2 Answers
Sodium hydrogencarbonate or sodium carbonate
Explanation:
This test works to distinguish between any alcohol and carboxylic acid.
You just add a small amount of sodium carbonate or sodium hydrogencarbonate (works just as well with other metals in the salt, i.e. potassium carbonate).
Due to the carbonate or hydrogencarbonate ion, and the hydrogen ion that dissociates from the carboxylic acid, it will form water and carbon dioxide, which can be shown by fizzing.
However, an alcohol doesn't have the property of a dissociating hydrogen ion, and so cannot react to form carbon dioxide and water.
pH meter or universal indicator!
Explanation:
Acetic (ethanoic) acid will have a pH of between 2.5 and 4.5, whilst ethanol will have pH of 7.0 - 7.3.
Universal indicator paper will show yellow/orange for acetic acid and green for ethanol.
