Tantalum facts for kids

	hafnium ← tantalum → tungsten
Appearance
	gray blue;
General properties
Name, symbol, number	tantalum, Ta, 73
Group, period, block	5, 6, d
Standard atomic weight	{{{atomic mass}}} g/mol
Electron configuration	[Xe] 4f14 5d3 6s2
Electrons per shell	2, 8, 18, 32, 11, 2 (Image)
Physical properties
Phase	solid
Density (near r.t.)	16.69 g/cm3
Liquid density at m.p.	15 g/cm3
Melting point	3290 K, 3017 °C, 5463 °F
Boiling point	5731 K, 5458 °C, 9856 °F
Heat of fusion	36.57 kJ/mol
Heat of vaporization	753 kJ/mol
Specific heat capacity	(25 °C) 25.36 J/(mol·K)
Vapor pressure
Atomic properties
Oxidation states	5, 4, 3, 2, 1, −1, −3; ((a mildly acidic oxide))
Electronegativity	1.5 (Pauling scale)
Ionization energies	1st: {{{1st ionization energy}}} kJ/mol
	2nd: {{{2nd ionization energy}}} kJ/mol
Atomic radius	146 pm
Covalent radius	170±8 pm
Miscellanea
Crystal structure	body-centered cubic
Crystal structure note	α-Ta
Magnetic ordering	paramagnetic
Electrical resistivity	(20 °C) 131Ω·m
Thermal conductivity	(300 K) 57.5 W/(m·K)
Thermal expansion	(25 °C) 6.3 µm/(m·K)
Speed of sound (thin rod)	(20 °C) 3400 m/s
Young's modulus	186 GPa
Shear modulus	69 GPa
Bulk modulus	200 GPa
Poisson ratio	0.34
Mohs hardness	6.5
Vickers hardness	870–1200 MPa
Brinell hardness	440–3430 MPa
CAS registry number	7440-25-7
Most stable isotopes
	Main article: Isotopes of tantalum
β−	180W

Tantalum in a glass tube

Tantalum is a chemical element. Tantalum was named tantalium. It has the chemical symbol Ta. It has the atomic number 73. It is a rare metal. It is hard and blue-gray. In chemistry it is placed in a group of metal elements named the transition metals.

Tantalum does not easily corrode. It is found in the mineral tantalite.

Images for kids

Ta(CH3)5.
Tantalite, Pilbara district, Australia
Tantalum electrolytic capacitor
Bimetallic coins minted by the Bank of Kazakhstan with silver ring and tantalum center.