Acetaldehyde semicarbazone is the semicarbazone derivative formed from acetaldehyde and semicarbazide. It is primarily used in analytical chemistry as a reference standard for the identification and characterization of acetaldehyde in carbonyl compounds. The compound's crystalline nature allows for purification, melting point determination, and structural analysis via spectroscopy, aiding in the confirmation of acetaldehyde presence in complex mixtures. It also serves as an intermediate in organic synthesis for the preparation of pharmaceuticals, agrochemicals, and heterocyclic compounds. In research laboratories, it is utilized to investigate reaction mechanisms related to hydrazone formation and the reactivity of imine derivatives.