Americium is a synthetic radioactive chemical element with the symbol Am and atomic number 95. It is a transuranic member of the actinide series, in the periodic table located under the lanthanide element europium and was thus named after the United States by analogy.
The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. 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.
Berkelium is a transuranic radioactive chemical element with the symbol Bk and atomic number 97. It is a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the Lawrence Berkeley National Laboratory where it was discovered in December 1949. Berkelium was the fifth transuranium element discovered after neptunium, plutonium, curium and americium.
Curium is a transuranic, radioactive chemical element with the symbol Cm and atomic number 96. This actinide element was named after eminent scientists Marie and Pierre Curie, both known for their research on radioactivity. Curium was first intentionally made by the team of Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso in 1944, using the cyclotron at Berkeley. They bombarded the newly discovered element plutonium with alpha particles. This was then sent to the Metallurgical Laboratory at University of Chicago where a tiny sample of curium was eventually separated and identified. The discovery was kept secret until after the end of World War II. The news was released to the public in November 1947. Most curium is produced by bombarding uranium or plutonium with neutrons in nuclear reactors – one tonne of spent nuclear fuel contains ~20 grams of curium.
Californium is a radioactive chemical element with the symbol Cf and atomic number 98. The element was first synthesized in 1950 at Lawrence Berkeley National Laboratory, by bombarding curium with alpha particles. It is an actinide element, the sixth transuranium element to be synthesized, and has the second-highest atomic mass of all elements that have been produced in amounts large enough to see with the naked eye. The element was named after the university and the U.S. state of California.
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst. The hydroxide ion forms salts, some of which dissociate in aqueous solution, liberating solvated hydroxide ions. Sodium hydroxide is a multi-million-ton per annum commodity chemical. The corresponding electrically neutral compound HO• is the hydroxyl radical. The corresponding covalently bound group –OH of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry.
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.
The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure.
Rubidium oxide is the chemical compound with the formula Rb2O. Rubidium oxide is highly reactive towards water, and therefore it would not be expected to occur naturally. The rubidium content in minerals is often calculated and quoted in terms of Rb2O. In reality, the rubidium is typically present as a component of (actually, an impurity in) silicate or aluminosilicate. A major source of rubidium is lepidolite, KLi2Al(Al,Si)3O10(F,OH)2, wherein Rb sometimes replaces K.
Curium(III) oxide is a compound composed of curium and oxygen with the chemical formula Cm2O3. It is a crystalline solid with a unit cell that contains two curium atoms and three oxygen atoms. The simplest synthesis equation involves the reaction of curium(III) metal with O2−: 2 Cm3+ + 3 O2− ---> Cm2O3. Curium trioxide can exist as five polymorphic forms. Two of the forms exist at extremely high temperatures, making it difficult for experimental studies to be done on the formation of their structures. The three other possible forms which curium sesquioxide can take are the body-centered cubic form, the monoclinic form, and the hexagonal form. Curium(III) oxide is either white or light tan in color and, while insoluble in water, is soluble in inorganic and mineral acids. Its synthesis was first recognized in 1955.
Berkelium forms a number of chemical compounds, where it normally exists in an oxidation state of +3 or +4, and behaves similarly to its lanthanide analogue, terbium. Like all actinides, berkelium easily dissolves in various aqueous inorganic acids, liberating gaseous hydrogen and converting into the trivalent oxidation state. This trivalent state is the most stable, especially in aqueous solutions, but tetravalent berkelium compounds are also known. The existence of divalent berkelium salts is uncertain and has only been reported in mixed lanthanum chloride-strontium chloride melts. Aqueous solutions of Bk3+ ions are green in most acids. The color of the Bk4+ ions is yellow in hydrochloric acid and orange-yellow in sulfuric acid. Berkelium does not react rapidly with oxygen at room temperature, possibly due to the formation of a protective oxide surface layer; however, it reacts with molten metals, hydrogen, halogens, chalcogens and pnictogens to form various binary compounds. Berkelium can also form several organometallic compounds.
Indium(III) hydroxide is the chemical compound with the formula In(OH)3. Its prime use is as a precursor to indium(III) oxide, In2O3. It is sometimes found as the rare mineral dzhalindite.
Curium(III) fluoride or curium trifluoride is the chemical compound composed of curium and fluorine with the formula CmF3. It is a white, nearly insoluble salt that has the same crystal structure as LaF3. It precipitates as a hydrate when fluoride ions are added to a weakly acidic Cm(III) solution; alternatively it can be synthesized by reacting hydrofluoric acid with Cm(OH)3. The anhydrous form is then obtained by desiccation or by treatment with hydrogen fluoride gas.
Americium(III) hydroxide is a radioactive inorganic compound with the chemical formula Am(OH)3. It consists of one americium atom and three hydroxy groups. It was first discovered in 1944, closely related to the Manhattan Project. However, these results were confidential and were only released to the public in 1945. It was the first isolated sample of an americium compound, and the first americium compound discovered.
Scandium(III) hydroxide is an inorganic compound with the chemical formula Sc(OH)3, the trivalent hydroxide of scandium. It is an amphoteric compound. It is slightly soluble in water, and its saturated solution contains Sc(OH)3 and a small amount of Sc(OH)+2. The solubility of scandium(III) hydroxide in water is 0.0279 mol/L. It will convert to ScO(OH) after aging, greatly reducing the solubility (0.0008 mol/L). Scandium(III) hydroxide can be produced by reacting scandium salts and alkali hydroxides. In the reaction, different starting ingredients can generate different intermediates such as Sc(OH)1.75Cl1.25, Sc(OH)2NO3 and Sc(OH)2.32(SO4)0.34.
Francium hydroxide is a hypothetical inorganic compound with a chemical formula FrOH. It is a hydroxide of francium.
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.
Curium compounds are compounds containing the element curium (Cm). Curium usually forms compounds in the +3 oxidation state, although compounds with curium in the +4, +5 and +6 oxidation states are also known.
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.
Curium(IV) oxide is an inorganic chemical compound of curium and oxygen with the chemical formula CmO2. Since all isotopes of curium are man-made, the compound does not occur in nature.
