Yttrium - Y General Information Discovery Yttrium was discovered by J. Gadolin in 1794 in Åbo, Finland, and named after the Swedish village Ytterby from which it was mined. Appearance Yttrium is a silvery-white, soft metal which is relatively stable in air due to formation of the oxide film. Source Yttrium occurs in nearly all the 'rare earth' minerals. It is recovered commercially from monazite sand and bastnaesite by reduction with calcium metal. Uses The largest use of yttrium is in the form of yttrium(Ill) oxide, which is used to produce phosphors which give the red colour in colour television tubes. It is also used in the making of microwave filters. Yttrium is often used as an additive in alloys, and increases the strength of aluminium and magnesium alloys. It is also used as a detoxifier for non-ferrous metals. It has been used as a catalyst in ethylene polymerisation. Yttrium-90, a radioactive isotope, has a dramatic medical use in needles which have replaced the surgeon's knife in killing pain-transmitting nerves in the spinal cord. Biological Role Yttrium has no known biological properties, and is non-toxic. It is a suspected carcinogen. General Information Yttrium reacts with water to give hydrogen. The finely divided metal is unstable in air; metal turnings ignite in air, in contrast to lump metal which is stable.

	Physical Information
	Atomic Number		39
	Relative Atomic Mass (12C=12.000)		88.906
	Melting Point/K		1795
	Boiling Point/K		3611
	Density/kg m-3		4469 (293K)
	Ground State Electron Configuration		[Kr]4d15s2
	Electron Affinity(M-M-)/kJ mol-1		+39

	Key Isotopes
	nuclide	88Y	89Y	90Y
	atomic mass	87.91	88.91
	natural abundance	0%	100%	0%
	half-life	106.6 days	stable	64 h

Other Information
Enthalpy of Fusion/kJ mol-1		17.2
Enthalpy of Vaporisation/kJ mol-1		367.4
Oxidation States
Y+3

	Ionisation Energies/kJ mol-1
	M - M+	616
	M+ - M2+	1181
	M2+ - M3+	1980
	M3+ - M4+	5963
	M4+ - M5+	7430
	M5+ - M6+	8970
	M6+ - M7+	11200
	M7+ - M8+	12400
	M8+ - M9+	14137
	M9+ - M10+	18400