Ethene Ethylene

CHEMICAL NAME = ethene CAS NUMBER = 74-85-1 MOLECULAR FORMULA = C2H4 MOLAR MASS = 28.1 g/mol COMPOSITION = C(85.6°/o) H(14.4%) 

LDPEs are flexible and include numerous plastic items such as plastic wraps (cellophane), grocery and trash bags, and diaper lining. 

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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 common property of coordinated alkenes is their susceptibility to attack by nucleophiles such as OH , OMe , MeC02, and Cl , and it has long been known that Zeise s salt is slowly attacked by non-acidic water to give MeCHO and Pt metal, while corresponding Pd complexes are even more reactive. This forms the basis of the Wacker process (developed by J. Smidt and his colleagues at Wacker Chemie, 1959-60) for converting ethene (ethylene) into ethanal (acetaldehyde) — see Panel overleaf. 

Athen, n. ethene (ethylene), -yl, n. ethenyl. Ather, m. ether (in older names frequently equivalent to ester). atberilhnlich, a. ether-Uke, ethereal. 

When there is more than one central atom, we consider the bonding about each atom independently. For example, to predict the shape of an ethene (ethylene)... 

Similar, but different, redeployment is envisaged when a carbon atom combines with three other atoms, e.g. in ethene (ethylene) (p. 8) three sp2 hybrid atomic orbitals disposed at 120° to each other in the same plane (plane trigonal hybridisation) are then employed. Finally, when carbon combines with two other atoms, e.g. in ethyne (acetylene) (p. 9) two sp1 hybrid atomic orbitals disposed at 180° to each other (idigonal hybridisation) are employed. In each case the s orbital is always involved as it is the one of lowest energy level. 

Ethene (ethylene) US produces 30 billion pounds ( 1,364 S HU) each year. 

Alkenes and alkynes are similar in structure to the alkanes except the alkenes contain a carbon-to-carbon double bond (C=C) and the alkynes contain a carbon-to-carbon triple bond (CsC). The name prefixes are exactly the same as for the alkanes with the same number of carbons, but the endings are -one for compounds widr double bonds and their derivatives and -yne for compounds with triple bonds and their derivatives. Ethene (ethylene) and propene (propylene) are alkenes. Ethyne (acetylene) is an alkyne. 

Acetic acid is used to produce the plastic polyethylene terephthalate (PET) (see Ethene [Ethylene]). Acetic acid is used to produce pharmaceuticals (see Acetylsalicylic Acid). 

There exist, however, compounds such as ethene (ethylene), C2H4, in which two electrons from each of the carbon atoms are mutually shared, thereby producing two two-electron bonds, an arrangement which is called a double bond. Each carbon in ethene is attached to only three other atoms ... 

When there is more than one central atom, the bonding about each atom is considered independently. For example, let s predict the shape of an ethene (ethylene) molecule, CH2=CH2. There are two centers in ethene to consider—the two carbon atoms. The first step is to write the Lewis structure (13). Each carbon atom has three regions of electron concentration on it two single bonds and one double bond. There are no lone pairs. The arrangement around each carbon atom is therefore trigo-... 

FIGURE 3.23 A view of the bonding pattern in ethene (ethylene), showing the framework of c-bonds and the single ir-bond formed by side-to-side overlap of unhybridized C2p-orbitals. The double bond is resistant to twisting because twisting would reduce the overlap between the two C2p-orbitals and weaken the Tr-bond. 

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