1 electron volt is the energy gained or lost by one electron when it
climbs or falls through a potential difference of 1 volt.
That amount of energy is 1.602 x 10⁻¹⁹ joule (rounded)
3 times that much energy is (3) x (1.602 x 10⁻¹⁹ joule) =
4.806 x 10⁻¹⁹ joule (rounded)
