absolute alcohol

A portion of the acid so obtained was further purified by dissolving in absolute alcohol and pouring into absolute ether.

The alcohol should be as concentrated as possible, even absolute alcohol is preferable.

Then add a sufficient quantity of absolute alcohol to make the solutions mix.

A glass capsule with tightly fitting (ground on) glass lid, containing clean cover-slips in absolute alcohol.

Wash well in distilled water till no more colour is discharged; if necessary, wash carefully with absolute alcohol.