Convert electronvolt to erg

The electronvolt is the energy an electron gains crossing one volt, 1.602 × 10⁻¹⁹ J, and is the natural unit of the very small. Chemical bonds and visible light are a few eV, X-rays tens of keV, nuclear gamma rays MeV, and the Large Hadron Collider brings protons to 6.8 TeV each. Through E = mc² it also serves as a mass unit: an electron is 0.511 MeV, a proton 938 MeV, and the Higgs boson 125 GeV.

The centimetre-gram-second system preceded the SI and its units linger in physics: the dyne is the force that accelerates one gram at 1 cm/s² (10⁻⁵ N), and the erg the work of one dyne over one centimetre (10⁻⁷ J), about the energy of a mosquito's wing beat. Astrophysics still writes luminosities in erg/s (the Sun: 3.8 × 10³³ erg/s), and surface tension is often quoted in dyn/cm, which equals mN/m.