Europium is a chemical element; it has symbol Eu and atomic number 63. Europium is a silvery-white metal of the lanthanide series that reacts readily with air to form a dark oxide coating. It is the most chemically reactive, least dense, and softest of the lanthanide elements. It is soft enough to be cut with a knife. Europium was isolated in 1901 and named after the continent of Europe. Europium usually assumes the oxidation state +3, like other members of the lanthanide series, but compounds having oxidation state +2 are also common. All europium compounds with oxidation state +2 are slightly reducing. Europium has no significant biological role and is relatively non-toxic compared to other heavy metals. Most applications of europium exploit the phosphorescence of europium compounds. Europium is one of the rarest of the rare-earth elements on Earth.
The lanthanide or lanthanoid series of chemical elements comprises at least the 14 metallic chemical elements with atomic numbers 57–70, from lanthanum through ytterbium. In the periodic table, they fill the 4f orbitals. Lutetium is also sometimes considered a lanthanide, despite being a d-block element and a transition metal.
Copper(II) nitrate describes any member of the family of inorganic compounds with the formula Cu(NO3)2(H2O)x. The hydrates are blue solids. Anhydrous copper nitrate forms blue-green crystals and sublimes in a vacuum at 150-200 °C. Common hydrates are the hemipentahydrate and trihydrate.
In chemistry, water(s) of crystallization or water(s) of hydration are water molecules that are present inside crystals. Water is often incorporated in the formation of crystals from aqueous solutions. In some contexts, water of crystallization is the total mass of water in a substance at a given temperature and is mostly present in a definite (stoichiometric) ratio. Classically, "water of crystallization" refers to water that is found in the crystalline framework of a metal complex or a salt, which is not directly bonded to the metal cation.
Europium(III) chloride is an inorganic compound with the formula EuCl3. The anhydrous compound is a yellow solid. Being hygroscopic it rapidly absorbs water to form a white crystalline hexahydrate, EuCl3·6H2O, which is colourless. The compound is used in research.
Iron(III) nitrate, or ferric nitrate, is the name used for a series of inorganic compounds with the formula Fe(NO3)3.(H2O)n. Most common is the nonahydrate Fe(NO3)3.(H2O)9. The hydrates are all pale colored, water-soluble paramagnetic salts.
Cerium nitrate refers to a family of nitrates of cerium in the +3 or +4 oxidation state. Often these compounds contain water, hydroxide, or hydronium ions in addition to cerium and nitrate. Double nitrates of cerium also exist.
Thorium(IV) nitrate is a chemical compound, a salt of thorium and nitric acid with the formula Th(NO3)4. A white solid in its anhydrous form, it can form tetra- and pentahydrates. As a salt of thorium it is weakly radioactive.
Yttrium(III) nitrate is an inorganic compound, a salt with the formula Y(NO3)3. The hexahydrate is the most common form commercially available.
Terbium(III) nitrate is an inorganic chemical compound, a salt of terbium and nitric acid, with the formula Tb(NO3)3. The hexahydrate crystallizes as triclinic colorless crystals with the formula [Tb(NO3)3(H2O)4]·2H2O. It can be used to synthesize materials with green emission.
Nitrate chlorides are mixed anion compounds that contain both nitrate (NO3−) and chloride (Cl−) ions. Various compounds are known, including amino acid salts, and also complexes from iron group, rare-earth, and actinide metals. Complexes are not usually identified as nitrate chlorides, and would be termed chlorido nitrato complexes.
Iron(II) nitrate is the nitrate salt of iron(II). It is commonly encountered as the green hexahydrate, Fe(NO3)2·6H2O, which is a metal aquo complex, however it is not commercially available unlike iron(III) nitrate due to its instability to air. The salt is soluble in water serves as a ready source of ferrous ions.
Lutetium(III) nitrate is an inorganic compound, a salt of lutetium and nitric acid with the chemical formula Lu(NO3)3. The compound forms colorless crystals, dissolves in water, and also forms crystalline hydrates. The compound is poisonous.
Europium(III) acetate is an inorganic salt of europium and acetic acid with the chemical formula of Eu(CH3COO)3. In this compound, europium exhibits the +3 oxidation state. It can exist in the anhydrous form, sesquihydrate and tetrahydrate. Its hydrate molecule is a dimer.
Europium(III) chromate is a chemical compound composed of europium, chromium and oxygen with europium in the +3 oxidation state, chromium in the +5 oxidation state and oxygen in the −2 oxidation state. It has the chemical formula of EuCrO4.
Europium compounds are compounds formed by the lanthanide metal europium (Eu). In these compounds, europium generally exhibits the +3 oxidation state, such as EuCl3, Eu(NO3)3 and Eu(CH3COO)3. Compounds with europium in the +2 oxidation state are also known. The +2 ion of europium is the most stable divalent ion of lanthanide metals in aqueous solution. Many europium compounds fluoresce under ultraviolet light due to the excitation of electrons to higher energy levels. Lipophilic europium complexes often feature acetylacetonate-like ligands, e.g., Eufod.
Terbium compounds are compounds formed by the lanthanide metal terbium (Tb). Terbium generally exhibits the +3 oxidation state in these compounds, such as in TbCl3, Tb(NO3)3 and Tb(CH3COO)3. Compounds with terbium in the +4 oxidation state are also known, such as TbO2 and BaTbF6. Terbium can also form compounds in the 0, +1 and +2 oxidation states.
Europium(III) iodide is an inorganic compound containing europium and iodine with the chemical formula EuI3.
Cobalt compounds are chemical compounds formed by cobalt with other elements.
Europium(III) carbonate is an inorganic compound with the chemical formula Eu2(CO3)3.
