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.
Structural Biochemistry/Molecular Geometry - VSEPR Theory. 1  Valence Shell Electron Pair Repulsion (VSEPR) theory Electron pairs around a central atom arrange themselves so that they can be as far apart as possible from each other. The valence shell is the outermost electron-occupied shell of an atom that holds the electrons involved in bonding. In a covalent bond, a pair of electrons is shared between two atoms. In a polyatomic molecule, several atoms are bonded to a central atom using two or more electron pairs.