To 0.25 mL or 0.25 g of the sample, add small thin slices of freshly cut sodium until no more will dissolve. Evolution of hydrogen gas indicates the presence of an acidic hydrogen, such as a hydroxyl group in an alcohol, a hydrogen attached to the nitrogen in a primary or secondary amine, or a hydrogen in a terminal alkyne. Cool the solution, and observe. Add an equal volume of ether. Another positive test is the formation of the solid salt. Liquid samples should be dried with calcium sulfate, prior to testing. This test may be applied to solid compounds or very viscous liquids by dissolving them in an inert solvent such as anhydrous ligroin or toluene.
Formation of hydrogen gas is a positive test.
Dealing with sodium metal can be exciting. Make sure that all samples are dry before proceeding with test.
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