covalent bond can bind either the same or different atoms.It is present in the molecules when they are in any state of aggregation, as well as between the atoms constituting the crystal lattice.In organic compounds, almost all the main types of bonds are covalent.
prefix "to" in the title this context means "joint participation", and "Valenta" - "joint action force."At its formation atomic shells of individual atoms form a single molecular orbital.The new molecular sheath is no longer possible to determine which of the electrons belong to one or another atom, they say that the electrons are socialized.
Covalent Bonding inherently saturability - atoms of one molecule could no longer bind to other atoms.In most cases, the dipole moment is not more than 1,0 D, and
for communication between the same atoms is zero or close to it.
One of the most important properties of a covalent bond is its constant spatial orientation.For example, in a covalently built symmetric molecules of methane angle between the bonds is constant and equal 109 ° 29 '.Covalent bonds are nitrogen, oxygen, phosphorus, sulfur and arsenic are defined as a direction in space.
covalent bond is very strong.Many inorganic compounds in which the crystals are formed with it, different hardness and refractory.Such compounds are often soluble in water or their solutions do not conduct electricity.
covalent bond is often formed by a pair of electrons located between atoms.It is also called lone pair, the remaining electrons form lone pairs which fill the shell and are not involved in binding.
If covalent bond is formed by the electron pair is only one of the reacting species, it is called coordination or donor-acceptor.In this case, an atom or ion that gives up its electron pair, is considered to be a donor, and one that summarizes the foreign electron pair is an acceptor.Coordination bond can also be formed when the two molecules.
polar covalent bond is intermediate between covalent and ionic.It can arise between two different types of atoms, but electrons are displaced not so much as in the case of ionic bond.This binding electron pair is not strictly in the middle between the nuclei, like a pure covalent bond.