<prompt> Ngo-1856 uKekulé waba ngu-Privatdozent e-University of Heidelberg. Ngo-1858 waqashwa njengoprofesa ogcwele e-University of Ghent, wabe esebizwa ngo-1867 eBonn, lapho ahlala khona impilo yakhe yonke. Ngokusekela imibono yakhe kulabo ababengaphambi kwakhe njengoWilliamson, Edward Frankland, William Odling, Auguste Laurent, Charles-Adolphe Wurtz nabanye, uKekulé wayengumqambi oyinhloko womqondo wesakhiwo samakhemikhali 185758. Lo mbono uvela emcabangweni we-atomic valence, ikakhulukazi i-tetravalence ye-carbon eyamenyezelwa nguKekulé ngasekupheleni kuka-1857 kanye nekhono lama-athomu e-carbon ukuxhuma komunye nomunye embula ephepheni elishicilelwe ngo-1858, kodwa ngo-1858 waqashwa njengoprofesa ophelele e-University of Ghent, wabe esebizelwa eBonn, lapho ahlala khona yonke imisebenzi yakhe esebenzayo esebenza khona. Kodwa-ke, ngokuqondene nemibono yokuqala yezinhlakazo zamakhemikhali  <response>: ukwakheka kwamakhemikhali 