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 shell electron pair repulsion (VSEPR) theory is a model used, in chemistry, to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms.he number of electron pairs in the valence shell of a central atom is determined after drawing the Lewis structure of the molecule, and expanding it to show all bonding groups and lone pairs of electrons.