b Structures in which all of the atoms have a complete valence shell of electrons are especially stable and make large contributions to the hybrid H2C—O—cH3 H2C=0 CH Less stable Stable Here this carbon Here the carbon atom has only six electrons atom has eight electronsb. Structures in which all of the atoms have a complete valence shell of electrons are especially stable and make large contributions to the hybrid. H2 C O CH3 + H2 C O CH3 + Here this carbon atom has only six electrons Here the carbon atom has eight electrons Less stable Stable