what is nickel ? and give its property
Answers
Answer:
Nickel is a chemical with a symbol NI.
properties..
Color. = silvery
PHase= Solid
Conductivity = Fairly good conductor of heat and electricity
Hardness = Harder than iron
Nickel is a chemical element with the symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel, powdered to maximize the reactive surface area, shows a significant chemical activity, but larger pieces are slow to react with air under standard conditions because an oxide layer forms on the surface and prevents further corrosion (passivation). Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks,[6][7] and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere.Physical properties
Phase at STP
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
−2, −1, +1,[2] +2, +3, +4[3] (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
(more)
Atomic radius
empirical: 124 pm
Covalent radius
124±4 pm
Van der Waals radius
163 pmOther properties
Natural occurrence
primordial
Crystal structure
face-centered cubic (fcc)Face-centered cubic crystal structure for nickel
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