An yttrium compound is a chemical compound containing yttrium (element symbol: Y). Among these compounds, yttrium generally has a +3 valence. The solubility properties of yttrium compounds are similar to those of the lanthanides. For example oxalates and carbonates are hardly soluble in water, but soluble in excess oxalate or carbonate solutions as complexes are formed. Sulfates and double sulfates are generally soluble. They resemble the "yttrium group" of heavy lanthanide elements.
The oxides and hydroxides of yttrium are yttrium oxide (Y2O3) and yttrium hydroxide (Y(OH)3), respectively, and they are both white solids which are hardly soluble in water. Among them, yttrium oxide can be prepared by heating yttrium carbonate or yttrium oxalate. Alternatively the oxychloride, Y3O4Cl can be heated in air to yield the oxide.
Yttrium hydroxide can be precipitated by the reaction of soluble yttrium compounds with sodium hydroxide or ammonia, and can also be obtained by the hydrolysis of yttrium alkoxide. Hydroxy acids and sugars present in the solution will prevent the formation of precipitates due to the formation of stable coordination compounds. Yttrium hydroxide can be decomposed by heating. Firstly, basic yttrium oxide (YO(OH)) is formed, and when heating is continued yttrium oxide is obtained. Both yttrium oxide and yttrium hydroxide are easily soluble in strong acids to form corresponding yttrium salts.
Yttrium chalcogenides Y2S3, Y2Se3, and Y2Te3 are known. They can be obtained by the direct combination of elementary substances or anhydrous chlorine. The reaction of compounds with chalcogenide gives: [9]
Yttrium halides can be obtained by reacting yttrium oxide, yttrium hydroxide or yttrium carbonate with the corresponding hydrohalic acid solution. For yttrium chloride (YCl3) and yttrium bromide (YBr3), the yttrium halide hydrate can be precipitated by cooling their saturated solution or by passing in the corresponding hydrogen halide. Yttrium halides, like lanthanide metal halides, cannot be obtained by direct heating of the hydrate, otherwise yttrium oxyhalide (YOX) will be formed. Anhydous compounds can be obtained by heating the hydrate in a hydrogen halide stream, or by treating it with ammonium halide and sulfoxide. [10] In addition to forming hydrates (YF3 · 1 / 2H2O, YCl3 · 6H2O, YBr3·6H2O, and YI3·8H2O), yttrium halides can also form complexes with some ligands. Substances, such as [Y(Me3PO)6]X3 or [Y(Me3AsO)6]X3 (X = Cl, Br, I) and the like with phosphine oxides. [11] Yttrium and halogens (except fluorine [12] ) or pseudohalogens can also form complexes, such as Cs3[Y2I9], (Bu4N)3 [Y(NCS)6 ], etc. [1]
The reaction of yttrium metal with yttrium chloride or yttrium bromide yields low-oxidation monohalides YX and yttrium sesquichloride Y2Cl3, and sesquibromide Y2Br3 (X = Cl, Br). [2]
Most of the salts from strong acids are soluble in water. The ionic radius (0.900) of yttrium in [Y(H2O)6]3+ is similar to that of holmium [Ho(H2O)6]3+ (0.901), and differs from easily hydrolyzed [Sc(H2O)6]3+. [3]
Yttrium carbonate and yttrium oxalate are sparingly soluble in water, but are dissolved in acid. They decompose on heating to yttrium oxide.
Organic acid salts of yttrium include yttrium formate, yttrium acetate, yttrium propionate, yttrium butyrate. They are all made by dissolving the carbonate or oxide in the corresponding acid. Aromatic polycarboxylates like phthalic acid or trimellitic acid have a rigid shape, and can coordinate more than one yttrium atom to form a metal-organic framework compound. [4] [5]
Two yttrium hydrides are known at standard conditions, YH2 and YH3. [6] YH9, a polyhydride is stable at high pressures, and is a superconductor at temperatures up to 243K. [7] [8]
Yttrium and pnictides can form compounds with the chemical formula YE (E = N, P, As, Sb). They can be hydrolyzed in humid air and emit volatile hydrides EH3.
Yttrium and carbon can form a variety of compounds, such as Y2C3, [9] YC2. [10] They can be made in several ways:
There are also several yttrium silicides, such as YSi2, [11] Y5Si4 and YSi; [12] and several stannides.
Yttrium and boron can also form many colourful compounds, such as gold YB4 , blue YB6 , light blue YB12. They are metallic; YB66 is a semiconductor, and the resistivity at room temperature is 106 Ω·cm. [13]
Lanthanum is a chemical element; it has symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table, of which lanthanum is the first and the prototype. Lanthanum is traditionally counted among the rare earth elements. Like most other rare earth elements, the usual oxidation state is +3, although some compounds are known with an oxidation state of +2. Lanthanum has no biological role in humans but is essential to some bacteria. It is not particularly toxic to humans but does show some antimicrobial activity.
Lutetium is a chemical element; it has symbol Lu and atomic number 71. It is a silvery white metal, which resists corrosion in dry air, but not in moist air. Lutetium is the last element in the lanthanide series, and it is traditionally counted among the rare earth elements; it can also be classified as the first element of the 6th-period transition metals.
Terbium is a chemical element; it has the symbol Tb and atomic number 65. It is a silvery-white, rare earth metal that is malleable, and ductile. The ninth member of the lanthanide series, terbium is a fairly electropositive metal that reacts with water, evolving hydrogen gas. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite.
Praseodymium(III) chloride is the inorganic compound with the formula PrCl3. Like other lanthanide trichlorides, it exists both in the anhydrous and hydrated forms. It is a blue-green solid that rapidly absorbs water on exposure to moist air to form a light green heptahydrate.
Neodymium(III) chloride or neodymium trichloride is a chemical compound of neodymium and chlorine with the formula NdCl3. This anhydrous compound is a mauve-colored solid that rapidly absorbs water on exposure to air to form a purple-colored hexahydrate, NdCl3·6H2O. Neodymium(III) chloride is produced from minerals monazite and bastnäsite using a complex multistage extraction process. The chloride has several important applications as an intermediate chemical for production of neodymium metal and neodymium-based lasers and optical fibers. Other applications include a catalyst in organic synthesis and in decomposition of waste water contamination, corrosion protection of aluminium and its alloys, and fluorescent labeling of organic molecules (DNA).
Yttrium(III) chloride is an inorganic compound of yttrium and chloride. It exists in two forms, the hydrate (YCl3(H2O)6) and an anhydrous form (YCl3). Both are colourless salts that are highly soluble in water and deliquescent.
Magnesium compounds are compounds formed by the element magnesium (Mg). These compounds are important to industry and biology, including magnesium carbonate, magnesium chloride, magnesium citrate, magnesium hydroxide, magnesium oxide, magnesium sulfate, and magnesium sulfate heptahydrate.
Scandium compounds are compounds containing the element scandium. The chemistry of scandium is almost completely dominated by the trivalent ion, Sc3+, due to its electron configuration, [Ar] 3d14s2. The radii of M3+ ions in the table below indicate that the chemical properties of scandium ions have more in common with yttrium ions than with aluminium ions. In part because of this similarity, scandium is often classified as a lanthanide-like element.
Many compounds of thorium are known: this is because thorium and uranium are the most stable and accessible actinides and are the only actinides that can be studied safely and legally in bulk in a normal laboratory. As such, they have the best-known chemistry of the actinides, along with that of plutonium, as the self-heating and radiation from them is not enough to cause radiolysis of chemical bonds as it is for the other actinides. While the later actinides from americium onwards are predominantly trivalent and behave more similarly to the corresponding lanthanides, as one would expect from periodic trends, the early actinides up to plutonium have relativistically destabilised and hence delocalised 5f and 6d electrons that participate in chemistry in a similar way to the early transition metals of group 3 through 8: thus, all their valence electrons can participate in chemical reactions, although this is not common for neptunium and plutonium.
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.
Aluminium (British and IUPAC spellings) or aluminum (North American spelling) combines characteristics of pre- and post-transition metals. Since it has few available electrons for metallic bonding, like its heavier group 13 congeners, it has the characteristic physical properties of a post-transition metal, with longer-than-expected interatomic distances. Furthermore, as Al3+ is a small and highly charged cation, it is strongly polarizing and aluminium compounds tend towards covalency; this behaviour is similar to that of beryllium (Be2+), an example of a diagonal relationship. However, unlike all other post-transition metals, the underlying core under aluminium's valence shell is that of the preceding noble gas, whereas for gallium and indium it is that of the preceding noble gas plus a filled d-subshell, and for thallium and nihonium it is that of the preceding noble gas plus filled d- and f-subshells. Hence, aluminium does not suffer the effects of incomplete shielding of valence electrons by inner electrons from the nucleus that its heavier congeners do. Aluminium's electropositive behavior, high affinity for oxygen, and highly negative standard electrode potential are all more similar to those of scandium, yttrium, lanthanum, and actinium, which have ds2 configurations of three valence electrons outside a noble gas core: aluminium is the most electropositive metal in its group. Aluminium also bears minor similarities to the metalloid boron in the same group; AlX3 compounds are valence isoelectronic to BX3 compounds (they have the same valence electronic structure), and both behave as Lewis acids and readily form adducts. Additionally, one of the main motifs of boron chemistry is regular icosahedral structures, and aluminium forms an important part of many icosahedral quasicrystal alloys, including the Al–Zn–Mg class.
Yttrium oxalate is an inorganic compound, a salt of yttrium and oxalic acid with the chemical formula Y2(C2O4)3. The compound does not dissolve in water and forms crystalline hydrates—colorless crystals.
Lanthanide trichlorides are a family of inorganic compound with the formula LnCl3, where Ln stands for a lanthanide metal. The trichlorides are standard reagents in applied and academic chemistry of the lanthanides. They exist as anhydrous solids and as hydrates.
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.
Promethium compounds are compounds containing the element promethium, which normally take the +3 oxidation state. Promethium belongs to the cerium group of lanthanides and is chemically very similar to the neighboring elements. Because of its instability, chemical studies of promethium are incomplete. Even though a few compounds have been synthesized, they are not fully studied; in general, they tend to be pink or red in color. Treatment of acidic solutions containing Pm3+ ions with ammonia results in a gelatinous light-brown sediment of hydroxide, Pm(OH)3, which is insoluble in water. When dissolved in hydrochloric acid, a water-soluble yellow salt, PmCl3, is produced; similarly, when dissolved in nitric acid, a nitrate results, Pm(NO3)3. The latter is also well-soluble; when dried, it forms pink crystals, similar to Nd(NO3)3. The electron configuration for Pm3+ is [Xe] 4f4, and the color of the ion is pink. The ground state term symbol is 5I4. The sulfate is slightly soluble, like the other cerium group sulfates. Cell parameters have been calculated for its octahydrate; they lead to conclusion that the density of Pm2(SO4)3·8 H2O is 2.86 g/cm3. The oxalate, Pm2(C2O4)3·10 H2O, has the lowest solubility of all lanthanide oxalates.
Lutetium compounds are compounds formed by the lanthanide metal lutetium (Lu). In these compounds, lutetium generally exhibits the +3 oxidation state, such as LuCl3, Lu2O3 and Lu2(SO4)3. Aqueous solutions of most lutetium salts are colorless and form white crystalline solids upon drying, with the common exception of the iodide. The soluble salts, such as nitrate, sulfate and acetate form hydrates upon crystallization. The oxide, hydroxide, fluoride, carbonate, phosphate and oxalate are insoluble in water.
Neptunium compounds are compounds containg the element neptunium (Np). Neptunium has five ionic oxidation states ranging from +3 to +7 when forming chemical compounds, which can be simultaneously observed in solutions. It is the heaviest actinide that can lose all its valence electrons in a stable compound. The most stable state in solution is +5, but the valence +4 is preferred in solid neptunium compounds. Neptunium metal is very reactive. Ions of neptunium are prone to hydrolysis and formation of coordination compounds.
Americium compounds are compounds containing the element americium (Am). These compounds can form in the +2, +3, and +4, although the +3 oxidation state is the most common. The +5, +6 and +7 oxidation states have also been reported.
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