Electronvolt
In physics, an electronvolt (symbol eV), also written as electron-volt and electron volt, is a unit of measurement equivalent to the amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in a vacuum. When used as a unit of energy, the numerical value of 1 eV expressed in unit of joules (symbol J) is equal to the numerical value of the charge of an electron in coulombs (symbol C).