View 3D animation of this reaction.

We illustrated this step using the 5 % NaOH extract. Had we used the NaHCO₃ extract from the separation step, CO₂ gas would evolve during acidification.

Note that the 4-methoxybenzoic acid* precipitated* at the bottom of the flask.

The pH of the solution may be checked with indicator* paper.

Check pH!