Answer – With atomic number 28, nickel’s electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸ or [Ar] 4s² 3d⁸.
Explanation:
Electronic configuration refers to the arrangement of electrons around the nucleus of an atom. Since every neutral atom has the same number of protons as electrons, the electron configuration of the atom of an element can be arrived at if provided its atomic number.
Electrons are distributed into orbitals of different shapes based on their energy levels, with the lowest energy orbitals being filled first (Aufbau’s principle). The order in which the orbitals are filled is based on the chart below:
Since Nickel has an atomic number of 28, it has 28 electrons. So its electron configuration will be 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸ as per the above chart. The last orbital has 8 electrons instead of 10 since Nickel has only 8 valence electrons.
Also, because Nickel follows the noble gas Argon, which has 18 electrons, in the periodic table, Ni electron configuration can also be written as [Ar] 4s² 3d⁸.
