Acid anhydrides yog cov seem seem tom qab oxoacid poob ib lossis ntau cov dej molecules. Feem ntau, rau inorganic acids, ib qho molecule ntawm cov kua qaub ncaj qha poob ib molecule ntawm dej los tsim nws cov anhydride coj; Nyob rau hauv cov txheej txheem no, lub xeev oxidation ntawm lub luag hauj lwm rau cov kua qaub acidity tseem unchanged. Organic acid anhydrides, conversely, yog tsim los ntawm intermolecular lub cev qhuav dej tshwm sim uas muaj ob los yog ntau tshaj molecules ntawm cov kua qaub. Tsuas yog oxoacids muaj cov anhydrides sib xws; oxygen-dawb acids tsis muaj.
Acid anhydrides feem ntau tuaj yeem raug saib raws li oxides muab los ntawm cov kua qaub los ntawm lub cev qhuav dej (txawm hais tias cov organic acid anhydrides tsis raug cais raws li oxides). Ntau cov anhydrides muaj peev xwm ntawm reacts nrog dej kom rov tsim cov kua qaub qub. Raws li qhov xwm txheej ntawm niam txiv acid, anhydrides tuaj yeem faib ua raws li hauv qab no: Inorganic acid anhydrides yog tsim los ntawm lub cev qhuav dej thiab condensation ntawm ib lossis ob lub kua qaub molecules-piv txwv li, carbonic anhydride (carbon dioxide, CO₂) thiab nitric anhydride (dinitrogen pentoxide, N₅O). Organic acid anhydrides yog cov tebchaw tsim los ntawm lub cev qhuav dej thiab condensation ntawm ob lub molecules ntawm monoacid lossis ib lub molecule ntawm diacid; Txawm hais tias lawv tsis yog oxides, lawv tseem hu ua acid anhydrides.
