A single covalent bond is created when two atoms share a pair of electrons. There is no net charge on either atom; the attractive force is produced by interaction of the electron pair with the nuclei of both atoms. If the atoms share more than two electrons, double and triple bonds are formed, because each shared pair produces its own bond. By sharing their electrons, both atoms are able to achieve a highly stable electron configuration corresponding to that of an inert gas. For example, in methane (CH4), carbon shares an electron pair with each hydrogen atom; the total number of electrons shared by carbon is eight, which corresponds to the number of electrons in the outer shell of neon; each hydrogen shares two electrons, which corresponds to the electron configuration of helium.
In most covalent bonds, each atom contributes one electron to the shared pair. In certain cases, however, both electrons come from the same atom. As a result, the bond has a partly ionic character and is called a coordinate link. Actually, the only purely covalent bond is that between two identical atoms.
Covalent bonds are of particular importance in organic chemistry because of the ability of the carbon atom to form four covalent bonds. These bonds are oriented in definite directions in space, giving rise to the complex geometry of organic molecules. If all four bonds are single, as in methane, the shape of the molecule is that of a tetrahedron. The importance of shared electron pairs was first realized by the American chemist G. N. Lewis (1916), who pointed out that very few stable molecules exist in which the total number of electrons is odd. His octet rule allows chemists to predict the most probable bond structure and charge distribution for molecules and ions. With the advent of quantum mechanics, it was realized that the electrons in a shared pair must have opposite spin, as required by the Pauli exclusion principle. The molecular orbital theory was developed to predict the exact distribution of the electron density in various molecular structures. The American chemist Linus Pauling introduced the concept of resonance to explain how stability is achieved when more than one reasonable molecular structure is possible: the actual molecule is a coherent mixture of the two structures.
2006-09-28 12:38:31
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answer #1
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answered by elucase 3
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The answer is a covalent bond. The two types of bonds are covalent and ionic. Ionic is formed when a positively charged atom is attracted to a negatively charged atom.
2006-09-28 16:57:19
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answer #2
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answered by brainster 2
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Covalent. actually skill sharing of electrons from the valence shell. it quite is significant observe, in spite of the undeniable fact that, that organic ionic bonding would not exist and all ionic bonding has some degree of covalence.
2016-10-18 04:01:23
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answer #3
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answered by Erika 4
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A covalent bond i think
2006-09-28 12:29:44
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answer #4
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answered by Anonymous
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covalenet bonds share electrons
2006-09-28 13:10:34
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answer #5
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answered by The Cheminator 5
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a covalent bond
2006-09-28 12:28:00
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answer #6
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answered by Anonymous
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covalent bond
2006-09-28 12:28:52
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answer #7
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answered by Anonymous
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we are doing this stuff in biology and i think that it is either ionic bonds or covalent bonds one of those two.
2006-09-28 12:28:19
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answer #8
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answered by dragonboy02nh 2
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to get a stable ,octet arrangement of electron..........
2006-09-28 12:58:23
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answer #9
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answered by Anonymous
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