The chemical symbol for Nickel is Ni and its atomic number is 28.
We find it listed in the periodic table of elements in group 10 and period 4, and block d.
Nickel belongs to the family of transition metals such as for example the Silver, the Bohrium, cadmium, ...
This element is stable.
Atomic number (Z) 28
Group, block group 10, d-block
Period: period 4
Element category: transition metal
Standard atomic weight (±) (Ar) 58.6934(4)
Electron configuration: [Ar] 3d8 4s2 or [Ar] 3d9 4s1
per shell: 2, 8, 16, 2 or 2, 8, 17, 1
Physical properties
Phase: solid
Melting point: 1728 K (1455 °C, 2651 °F)
Boiling point: 3003 K (2730 °C, 4946 °F)
Density near r.t. : 8.908 g/cm3
when liquid, at m.p. 7.81 g/cm3
Heat of fusion: 17.48 kJ/mol
Heat of vaporization: 379 kJ/mol
Molar heat capacity: 26.07 J/(mol·K)
Atomic properties
Oxidation states: 4, 3, 2, 1, −1, −2 (a mildly basic oxide)
Electronegativity: Pauling scale: 1.91
Ionization energies 1st: 737.1 kJ/mol
2nd: 1753.0 kJ/mol
3rd: 3395 kJ/mol
Atomic radius empirical: 124 pm
Covalent radius: 124±4 pm
Van der Waals radius: 163 pm
Element crystal structure: face-centered cubic.
Speed of sound thin rod: 4900 m/s (at r.t.)
Thermal expansion: 13.4 µm/(m·K) (at 25 °C)
Thermal conductivity: 90.9 W/(m·K)
Electrical resistivity: 69.3 nΩ·m (at 20 °C)
Magnetic ordering: ferromagnetic
Young's modulus: 200 GPa
Shear modulus: 76 GPa
Bulk modulus: 180 GPa
Poisson ratio: 0.31
Mohs hardness: 4.0
Vickers hardness: 638 MPa
Brinell hardness: 667–1600 MPa
CAS Number: 7440-02-0