分子中的碳基(
)跟gen兩liang個ge相xiang同tong或huo不bu同tong的de烴ting基ji連lian接jie,這zhe種zhong化hua合he物wu叫jiao酮tong。酮tong分fen子zi中zhong的de羰tang基ji也ye叫jiao酮tong基ji,它ta是shi酮tong的de官guan能neng團tuan。酮tong分fen子zi中zhong的de兩liang個ge烴ting基ji相xiang同tong的de叫jiao單dan酮tong,不bu同tong的de叫jiao混hun酮tong。酮tong能neng跟gen親qin核he試shi劑ji發fa生sheng羰tang基ji的de加jia成cheng反fan應ying。酮tong加jia氫qing可ke還hai原yuan成cheng相xiang應ying的de仲zhong醇chun。酮tong不bu如ru醛quan活huo潑po,不bu容rong易yi被bei較jiao弱ruo的de氧yang化hua劑ji(如多倫試劑、費林試劑)氧化,遇強氧化劑(如高錳酸鉀、硝酸)時被氧化,碳鏈斷裂而生成碳原子數較少的羧酸。