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Europium is a chemical element; it has symbol Eu and atomic number 63. It is a silvery-white metal of the lanthanide series that reacts readily with air to form a dark oxide coating. Europium is the most chemically reactive, least dense, and softest of the lanthanides. It is soft enough to be cut with a knife.
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.
Phosphorescent materials were discovered in the 1700s, and people have been studying them and making improvements over the centuries.The development of strontium aluminate pigments in 1993 was spurred on by the need to find a substitute for glow-in-the-dark materials with high luminance and long phosphorescence, especially those that used promethium.
The real element 99, einsteinium, has no such qualities. Element 115 Ufology, various works Widely known within the sci-fi and UFO community; since, according to ufologist Bob Lazar, it is used by alien engines to generate anti-gravity and propulsion. The real element 115 is moscovium, a synthetic element with an extremely short half-life ...
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 is exempt of this classification as it has two valence states: Eu 2+ and Eu 3+. [29] Yttrium is grouped as heavy rare-earth element due to chemical similarities. [30] The break between the two groups is sometimes put elsewhere, such as between elements 63 (europium) and 64 (gadolinium). [31]
Americium is a synthetic chemical element; it has symbol Am and atomic number 95. It is radioactive and a transuranic member of the actinide series in the periodic table, located under the lanthanide element europium and was thus named after the Americas by analogy.
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. It is also an agent for the manufacture of fluorescent glass. Europium fluorescence is used in the anti-counterfeiting phosphors in ...