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No europium-dominant minerals are known yet, despite a single find of a tiny possible Eu–O or Eu–O–C system phase in the Moon's regolith. [ citation needed ] Depletion or enrichment of europium in minerals relative to other rare-earth elements is known as the europium anomaly . [ 23 ]
Naturally occurring europium (63 Eu) is composed of two isotopes, 151 Eu and 153 Eu, with 153 Eu being the most abundant (52.2% natural abundance).While 153 Eu is observationally stable (theoretically can undergo alpha decay with half-life over 5.5×10 17 years), 151 Eu was found in 2007 to be unstable and undergo alpha decay. [4]
Europium compounds fluoresce under UV light at 395 nm and 365 nm. [1] Europium compounds are compounds formed by the lanthanide metal europium (Eu). In these compounds, europium generally exhibits the +3 oxidation state, such as EuCl 3, Eu(NO 3) 3 and Eu(CH 3 COO) 3. Compounds with europium in the +2 oxidation state are also known.
Rare-earth element abundances of basalts, of both terrestrial and lunar origins [1]. The europium anomaly is the phenomenon whereby the europium (Eu) concentration in a mineral is either enriched or depleted relative to some standard, commonly a chondrite or mid-ocean ridge basalt (MORB).
Europium(II) sulfide is the inorganic compound with the chemical formula EuS. It is a black, air-stable powder . Europium possesses an oxidation state of +II in europium sulfide, whereas the lanthanides exhibit a typical oxidation state of +III. [ 1 ]
Europium(III) hydroxide can be prepared by reacting metallic europium with water. It reacts with acids and produces europium(III) salts: Eu(OH) 3 + 3 H + → Eu 3+ + 3 H 2 O. Europium(III) hydroxide decomposes to EuO(OH) at elevated temperature. Further decomposition produces Eu 2 O 3. [1]
Treating Eu 2 O 3 with aqueous HCl produces hydrated europium chloride (EuCl 3 ·6H 2 O). This salt cannot be rendered anhydrous by heating. Instead one obtains an oxychloride. Anhydrous EuCl 3 is often prepared by the "ammonium chloride route," starting from either Eu 2 O 3 [1] [2] or hydrated europium chloride (EuCl 3 ·6H 2 O) by heating ...
Europium(III) oxide (Eu 2 O 3), is a chemical compound of europium and oxygen. It is widely used as a red or blue phosphor in television sets and fluorescent lamps , and as an activator for yttrium -based phosphors.