What are Epididymitis and Orchitis? Pain in the scrotum or testicle (âtesteâ) might be from epididymitis, orchitis or both. Epididymitis is swelling or pain in the back of the testicle in the coiled tube (epididymis) that stores and carries sperm.
Share. By Anne Marie Helmenstine, Ph.D. Definition: Valence bond theory is a chemical bonding theory that explains the bonding between two atoms is caused by the overlap of half-filled atomic orbitals. The two atoms share each other's unpaired electron to form a filled orbital to form a hybrid orbital and bond together.
Valence Definition. Valence is typically, the number of electrons needed to fill the outermost shell of an atom. Because exceptions exist, the more general definition of valence is the number of electrons with which a given atom generally bonds or number of bonds an atom forms. (Think iron, which may have a valence of 2 or a valence of 3.) The IUPAC formal definition of valence is the maximum number of univalent atoms that may combine with an atom. Usually, the definition is based on the maximum number of either hydrogen atom or chlorine atoms. Note the IUPAC only defines a single valence value (the maximum), while atoms are known to be capable of displaying more than one valence. For example, copper commonly carries a valence of 1 or 2.