Atomic number:39

Group numbers:3

Period:5

Electronic configuration:[Kr] 4d¹ 5s²

Formal oxidation number:+3

Electronegativities:1.22

Atomic radius / pm:177.6

Relative atomic mass:88.90585 ± 0.00002

 

Yttrium was discovered by Johan Gadolin (FI) in 1794. Named after Ytterby, a village in Sweden. It is a silvery, ductile, fairly reactive metal that is easily combustible, reacts with oxygen in water to release hydrogen. Exposed surfaces form oxide film. Yttrium is found in minerals such as monazite, xenotime and yttria. It is combined with europium to make red phosphors for colour TV's. Yttrium oxide and iron oxide combine to form a crystal garnet used in radar.

Density / g dm^-3:4469 (293 K)

Molar volume / cm³mol^-1:19.89 (293 K)

Electrical resistivity / μΩcm:57 (20 °C)

Thermal conductivity / W m^-1K^-1:17.2

Melting point / °C:1522

Boiling point / °C:3345

Heat of fusion / kJ mol^-1:17.2

Heat of vaporization / kJ mol^-1:367.4

Heat of atomization / kJ mol^-1:420.45

1st ionization energy / kJ mol^-1:599.86

2nd ionization energy / kJ mol^-1:1180.99

3rd ionization energy / kJ mol^-1:1979.89

in the atmosphere / ppm:-

in the Earth's crust / ppm:20

in the oceans / ppm:0.0003