Rau cov inorganic acids, cov oxide ntawm cov tsis yog -hlau keeb- muab nws nyob rau hauv tib oxidation lub xeev raws li nyob rau hauv cov kua qaub - ua cov kua qaub anhydride. Piv txwv li, hauv carbonic acid, carbon muaj oxidation xeev ntawm +4; Yog li ntawd, nws cov kua qaub anhydride yog carbon dioxide.
Rau cov organic acids, cov anhydride tuaj yeem muab tau los ntawm kev ua kom lub cev qhuav dej: ua ntej, ib qho stoichiometric coefficient tau muab tso ua ntej cov kua qaub kua qaub los xyuas kom meej cov naj npawb ntawm hydrogen ions dhau los ua tus lej (cov kauj ruam no tsis tsim nyog yog tias suav yog twb tseem); Tom qab ntawd, ib lossis ntau lub molecules ntawm H₂O raug tshem tawm. Piv txwv li, CH₃COOH tsuas muaj ib qho hydrogen ion xwb; los ntawm thawj prefixing nws nrog lub stoichiometric coefficient 2, thiab ces tshem tawm ib molecule ntawm H₂O, peb tau txais (CH₃CO)₂O, uas yog nws cov kua qaub anhydride. Los ntawm tib lub ntsiab lus, yog tias cov kua qaub muaj peb cov hydrogen ions, ib qho yuav siv cov stoichiometric coefficient ntawm 2 thiab tom qab ntawd tshem tawm peb cov dej molecules.
Aluminium oxide (Al₂O₃) yog tsim los ntawm lub cev qhuav dej ntawm txhuas hydroxide [Al(OH)₃]. Qhov no tshwm sim vim tias txhuas hydroxide tuaj yeem hloov kho raws li HalO₂·H₂O (meta-aluminic acid); Thaum lub cev qhuav dej, nws yields aluminium oxide [tshwj xeeb: 2(HalO₂·H₂O) → Al₂O₃·2H₂O (lub cev qhuav dej) → Al₂O₃].
