28Nickel

Nickel is a transition metal in group 10, period 4. At 25 °C it is a solid.

Shells: 2, 8, 16, 2. A simple picture: electrons do not move in circles.

Symbol: Ni
Atomic number: 28 protons in the nucleus
Standard atomic weight: 58.693 ± 0.001The isotope mix varies in normal samples, so the value cannot be given more precisely.
Electron configuration: [Ar] 3d⁸ 4s²
Electrons in each shell: 2, 8, 16, 2
Group, period, block: 10, 4, d
Family: Transition metals
State at 25 °C: solid
Electronegativity: 1.91 (Pauling scale)
First ionisation energy: 737.1 kJ/mol (7.639878 eV)

Where these numbers come from

Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.