It is a white solid, although commercial samples appear gray.

It is sold commercially as a slurry (~35%) in mineral oil or sometimes paraffin wax to facilitate dispensing.

[3] Potassium hydride is produced by direct combination of the metal and hydrogen at temperatures between 200 and 350 °C: This reaction was discovered by Humphry Davy soon after his 1807 discovery of potassium, when he noted that the metal would vaporize in a current of hydrogen when heated just below its boiling point.

It also deprotonates amines to give the corresponding amides of the type KNHR and KNR2.

[6] KH can be pyrophoric in air, react violently with acids, and can ignite upon contact with oxidants.