1858 ~ 1861, Kekulé, Couper, and Butlerov, laid the basis for one of the most fundamental theories in chemistry: the structural theory. Valence(化合价): C — tetravalent; O — divalent; H — monovalent
Stanley E. Manahan is Professor of Chemistry at the University of MissouriColumbia, where he has been on the faculty since 1965 and is President of ChemChar Research, Inc., a firm developing non-incinerative thermochemical waste treatment