Electron Configuration Of Calcium Ion. What is the electron configuration of a sodium atom after it loses an electron? The electron configuration for gallium, ga is 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^1 gallium, ga has 31 protons and 31 electrons.
1s2 2s2 2p6 3s2 3p6. This means that in a neutral calcium atom, there are 20 protons in its nucleus. So the fluoride anion is going to have an electron configuration of 1s two, 2s two, 2p, now it's going to have an extra electron here, 2p six.
However, notice that 1s 2 2s 2 2p 6 3s 2 3p 6 is the configuration for argon, a noble gas.
So that would be 18 electrons. The last electron is in the 4th period, in the p region and the first electron in that region. The sum of these superscripts should equal the atomic number for a neutral atom. What is the electron configuration of a calcium ion?