Covalent bonding triple bonds

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 ... 

In Table VI3) and Fig. 3 there are given radii for use in compounds of this type. The sum of the singlebond radii for two atoms gives the expected distance between these two atoms in such a compound when they are connected by a covalent bond. The sum of their double-bond or triple-bond radii similarly gives the expected distance when they are connected by a double or a triple bond. 

Carbon likes to form bonds so well with itself that it can form multiple bonds to satisfy its valence of four. When two carbon atoms are linked with a single bond and their other valencies (three each) are satisfied by hydrogens, the compound is ethane. When two carbons are linked by a double bond (two covalent bonds) and their other valencies (two each) are satisfied by hydrogens, the compound is ethylene. When two carbons are linked by a triple bond (three covalent bonds) and their other valencies (one each) are satisfied by hydrogens, the compound is acetylene. 

Triple bond A covalent bond formed when six electrons are shared between two atoms. 

Distinguish between each of the following pairs (a) an ion and an ionic bond, (b) an ion and a free atom, (c) a covalent bond and an ionic bond, (cl) a triple bond and three single bonds on the same atom, (e) a polyatomic molecule and a polyatomic ion. 

Every group of electrons shared between two atoms constitutes a covalent bond. When one pair of electrons is involved, the bond is called a single bond. When two pairs of electrons unite two atoms, the bond is called a double bond. Three pairs of electrons shared between two atoms constitute a triple bond. Examples of these types of bonds arc given below ... 

There are several, separate types of interaction in III both covalent bonds and dipoles. Induced dipoles involve a partial charge, which we called <5+ or S, but, by contrast, covalent bonds involve whole numbers of electrons. A normal covalent bond, such as that between a hydrogen atom and one of the carbon atoms in the backbone of III, requires two electrons. A double bond consists simply of two covalent bonds, so four electrons are shared. Six electrons are incorporated in each of the rare instances of a covalent triple bond . A few quadruple bonds occur in organometallic chemistry, but we will ignore them here. 

Covalent bonding is the sharing of one or more pairs of electrons by two atoms. The covalent bonds in a molecule a covalently bonded compound are represented by a dash. Each dash is a shared pair of electrons. These covalent bonds may be single bonds, one pair of shared electrons as in H-H double bonds, two shared pairs of electrons as in H2C=CH2 or triple bonds, three shared pairs of electrons, N=N . It is the same driving force to form a covalent bond as an ionic bond—completion of the atom s octet. In the case of the covalent bond, the sharing of electrons leads to both atom utilizing the electrons towards their octet. 

In ethylene, there are two types of bonds. Sigma (tr) bonds have the overlap of the orbitals on a line between the two atoms involved in the covalent bond. In ethylene, the C-H bonds and one of the C-C bonds are sigma bonds. Pi (ir) bonds have the overlap of orbitals above and below a line through the two nuclei of the atoms involved in the bond. A double bond is always composed of one sigma and one pi bond. A carbon-to-carbon triple bond results from the... 

For most commercial polymers, carbon and silicon are the two backbone building blocks, and they routinely form chains of like atoms. Generally three types of covalent bonds are associated with carbon in the production of commercial vinyl polymers, as shown in Fig. 2.5 the single, double, and triple carbon-to-carbon bonds. 

HCNO appears to take part in more than four covalent bonds an almost triple bond between C and N ( j/3 and /6 account for one of the components of this bond, which would be of n symmetry in linear HCNO), a o bond between N and O, and a highly polar bond between N and O (of n symmetry in linear HCNO, described here by /i and /5). The remaining two orbitals, j/2 and /4, form the ethyne bond (of k symmetry in linear C2H2) that is broken during the reaction. 

These covalent bond lengths are reasonably constant among molecules, as the paraffin C—C bond usually has a length of 154 pm, the olefin C=C double bond has a length of 134 pm, and the acetylenic triple bond has a length of 120 pm. The C—H bond is 109 pm in a paraffin and 105 pm in an acetylene. 

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