氢化 qīnghuà hydrogenation Origin Definitions Defs Strokes Stroke Words Sentences Sents 碳氢化合物 tànqīnghuàhéwù hydrocarbon 氢化氰 qīnghuàqíng hydrogen cyanide a highly toxic chemical compound with the formula HCN, occurring as a colorless gas or as hydrocyanic acid when in solution