Atomic number:67

Group numbers:3

Period:6

Electronic configuration:[Xe] 4f¹¹ 6s²

Formal oxidation number:+3

Electronegativities:1.23

Atomic radius / pm:174.3

Relative atomic mass:164.93032 ± 0.00002

 

Holmium was discovered by Per Theodore Cleve (SE) in 1879. The origin of the name comes from the Greek word Holmia meaning Stockholm. It is a fairly soft, malleable, lustrous, silvery metal that reacts slowly with oxygen and water. Holmium dissolves in acids and is able to react violently with air or halogens. Holmium occurs in gadolinite but most often it's produced from monazite sand. It has very few practical applications; however, it has some unusual magnetic properties that offer some hope for future applications.

Density / g dm^-3:8795 (298 K)

Molar volume / cm³mol^-1:18.75 (298 K)

Electrical resistivity / μΩcm:87 (20 °C)

Thermal conductivity / W m^-1K^-1:16.2

Melting point / °C:1474

Boiling point / °C:2700

Heat of fusion / kJ mol^-1:17.2

Heat of vaporization / kJ mol^-1:303

Heat of atomization / kJ mol^-1:302.63

1st ionization energy / kJ mol^-1:580.99

2nd ionization energy / kJ mol^-1:1138.54

3rd ionization energy / kJ mol^-1:2203.74

in the atmosphere / ppm:-

in the Earth's crust / ppm:0.78

in the oceans / ppm:0.00000008