Adding acid-base indicator, formic acid or acetic acid is obviously acidic, then adding acidic potassium permanganate solution, slightly heating, formic acid bubbling (carbon dioxide), and the rest is acetic acid;

Adding silver ammonia solution, heating in water bath, and generating formaldehyde when there is a silver mirror.

Adding periodic acid, heating slightly, neutralizing the solution to neutrality, and then using silver ammonia solution and ethylene glycol with silver mirror (ethylene glycol will be oxidized to break carbon-carbon single bond to obtain glyoxal);

Adding acidic potassium permanganate solution (excessive), slightly heating, methanol foaming, ethanol fading but not foaming,

The rest are acetone and tert-butanol, which can be detected by Lucas reagent.

Pay attention to these inspection methods, such as smelling, measuring boiling point and comparing viscosity. These are all good physical methods.

If you feel bad, you can ask me again.