Ethylene covalent bond formation

Covalent bond formation in ethylene, (a) Lewis structure, (b) overlap of sf hybrid orbitals forms a sigma [Pg.25]

Covalent bond formation in ethylene (CHjCHj). (a) Lewis structure, (b) Overlap oisp hybrid orbitals on adjacent carbons forms a C—C cr bond (see Figure 1.18), and overlap of carbon sp hybrid orbitals on carbons with 1 orbitals on hydrogens gives C—H [Pg.73]

Double and triple covalent bonds can be formed between elements by the sharing of two or three electron pairs respectively. Consider the formation of ethene (ethylene), C2H4 ... 

A recent study (1) has demonstrated that the electrochemical oxidation of hydroxide ion yields hydroxyl radical ( OH) and its anion (O"-). These species in turn are stabilized at glassy carbon electrodes by transition-metal ions via the formation of metal-oxygen covalent bonds (unpaired d electron with unpaired p electron of -OH and O- ). The coinage metals (Cu, Ag, and Au), which are used as oxygen activation catalysts for several industrial processes (e.g., Ag/02 for production of ethylene oxide) (2-10), have an unpaired electron (d10s1 or d9s2 valence-... 

Stretched and twisted ethylene again may serve as examples. As the H—H separation decreases, and as the twist angle in ethylene decreases, the covalent perturbation y increases in absolute magnitude. In both cases, this results in a stabilization of the Sg state (bond formation) relative to the antibonding T state. It also results in the stabilization of the S, and S2 states of H2, although in the usual description the first of these states has as many electrons in the antibonding as in the bonding orbital, and the second only... 

The majority of investigations have been concerned with the dehydration of ethyl alcohol. Controversy has raged for many years over the possibility that diethyl ether is a precursor in the formation of ethylene. The inconsistency in the conclusions may arise from a failure of the earlier workers to appreciate the importance of the intrinsic acidity of the alumina. Whereas Balaceanu and Jungers regard diethyl ether as the precursor of ethylene (169), Brey and KriegeT prefer simultaneous reactions (170), a mechanism favoured by Topchieva et al. who further suggested a covalently bonded intermediate (171). 

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