Covalent bonds form when atoms share their valence electrons with other atoms to become a more stable molecule. Atoms share their electrons in order to completely fill up their outer-most layer — the valence shell. Two atoms that are covalently bonded have less energy than the individual atoms, making the bonded atoms more stable.Know More
Atoms form covalent bonds as a result of the Octet Rule. The Octet Rule states that all atoms in a molecule need to have eight electrons in their valence shell. This rule can be satisfied by sharing, losing or gaining electrons. A covalent bond allows atoms to satisfy the Octet Rule via sharing.
The reason atoms in covalent bonds satisfy the Octet Rule through sharing rather than losing or gaining electrons is because covalent bonds form between atoms with similar electronegativities. Electronegativity measures the tendency of an atom to attract electrons. Atoms with similar electronegativities are more willing to share electrons than those with different electronegativities.
Up to three covalent bonds can form at one time in a molecule. In a single bond, one pair of electrons is shared between two atoms. A double bond shares two pairs of electrons; it is stronger than a single bond, but it also creates a less stable molecule because it is more reactive. The triple bond shares three pairs of electrons, making it the least stable covalent bond.Learn more about Atoms & Molecules
Nitrogen can form up to four covalent bonds, most commonly seen in ammonium. Ammonium is a positive ion, which isn't as stable as ammonia, which has only three covalent bonds.Full Answer >
Chemical bonds are formed when unstable, reactive atoms seek out stable configurations through sharing, donating or receiving valence electrons from other atoms. Bonds are broken down when a specific amount of energy known as the bond energy is applied to the bond.Full Answer >
The chemical elements most likely to form covalent bonds are those that share electrons, such as carbon, as opposed to those that take them from another element to form an ionic bond. In general, they are nonmetals with similar electronegativities. They are located toward the center of the periodic table, according to HowStuffWorks.Full Answer >
Atoms that typically form covalent bonds with each other have similar electronegativity, which expresses the atom's tendency to attract electrons, such as with carbon and hydrogen, which form methane. They stand in contrast to ionic bonds, where electronegativities are vastly different, as with sodium and chlorine, which combine to form table salt. These actually exist on a continuum with significant but lesser differences in electronegativity causing the formation of polar molecules.Full Answer >