The second orbit for the only electron in a He+ ion has a radius of 5.29 X 10^-11 m. What is the speed of an electron in that orbit? Remember, a helium ion has two protons, each with a charge of +1.6 X 10^-19 C, and one electron with a charge of -1.6 X 10^-19 C. The mass of the electron is 9.1 X 10^-31 kg.