An oxime is a derivative of an aldehyde or a ketone (termed aldoxime and ketoxime, respectively) formed by the condensation with hydroxylamine (NH₂OH), and containing the group C=N–OH. Being easily isolated and with characteristic melting points, oximes are used in qualitative analysis for identification of aldehydes and ketones. For example, acetaldehyde (ethanal) forms the aldoxime CH₃CH=NOH, and acetone (propanone) forms the ketoxime (CH₃)₂C=NOH. Ketoximes undergo the Beckmann rearrangement.