The actinide or actinoid series encompasses the 14 metallic chemical elements with atomic numbers from 89 to 102, actinium through nobelium. The actinide series derives its name from the first element in the series, actinium. The informal chemical symbol An is used in general discussions of actinide chemistry to refer to any actinide.
Neptunium is a chemical element with the symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it being named after Neptune, the next planet beyond Uranus. A neptunium atom has 93 protons and 93 electrons, of which seven are valence electrons. Neptunium metal is silvery and tarnishes when exposed to air. The element occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, poisonous, pyrophoric, and capable of accumulating in bones, which makes the handling of neptunium dangerous.
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.
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.
Mercury(I) nitrate is an inorganic compound, a salt of mercury and nitric acid with the formula Hg2(NO3)2. A yellow solid, the compound is used as a precursor to other Hg22+ complexes. The structure of the hydrate has been determined by X-ray crystallography. It consists of a [H2O-Hg-Hg-OH2]2+ center, with a Hg-Hg distance of 254 pm.
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.
Titanium nitrate is the inorganic compound with formula Ti(NO3)4. It is a colorless, diamagnetic solid that sublimes readily. It is an unusual example of a volatile binary transition metal nitrate. Ill defined species called titanium nitrate are produced upon dissolution of titanium or its oxides in nitric acid.
Zirconium nitrate is a volatile anhydrous transition metal nitrate salt of zirconium with formula Zr(NO3)4. It has alternate names of zirconium tetranitrate, or zirconium(IV) nitrate.
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.
Indium(III) nitrate is a nitrate salt of indium which forms various hydrates. Only the pentahydrate has been crystallographically verified. Other hydrates are also reported in literature, such as the trihydrate.
Neptunium (IV) oxalate is an inorganic compound, a salt of neptunium and oxalic acid with the chemical formula Np(C2O4)2. The compound is slightly soluble in water, forms crystalline hydrates—green crystals.
Plutonium (IV) nitrate is an inorganic compound, a salt of plutonium and nitric acid with the chemical formula Pu(NO3)4. The compound dissolves in water and forms crystalline hydrates as dark green crystals.
Holmium (III) nitrate is an inorganic compound, a salt of holmium and nitric acid with the chemical formula Ho(NO3)3. The compound forms yellowish crystals, dissolves in water, also forms crystalline hydrates.
Ytterbium(III) nitrate is an inorganic compound, a salt of ytterbium and nitric acid with the chemical formula Yb(NO3)3. The compound forms colorless crystals, dissolves in water, and also forms crystalline hydrates.
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.
Erbium(III) nitrate is an inorganic compound, a salt of erbium and nitric acid with the chemical formula Er(NO3)3. The compound forms pink crystals, readily soluble in water, also forms crystalline hydrates.
Thulium(III) nitrate is an inorganic compound, a salt of thulium and nitric acid with the chemical formula Tm(NO3)3. The compound forms dark-green crystals, readily soluble in water, also forms crystalline hydrates.
Polonium tetranitrate is an inorganic compound, a salt of polonium and nitric acid with the chemical formula Po(NO3)4. The compound is radioactive, forms white crystals.
A transition metal nitrate complex is a coordination compound containing one or more nitrate ligands. Such complexes are common starting reagents for the preparation of other compounds.
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.
