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Actinium is a chemical element; it has symbol Ac and atomic number 89. It was first isolated by Friedrich Oskar Giesel in 1902, who gave it the name emanium; the element got its name by being wrongly identified with a substance André-Louis Debierne found in 1899 and called actinium. The actinide series, a set of 15 elements between actinium ...
The actinide series is a group of chemical elements with atomic numbers ranging from 89 to 102, [note 1] including notable elements such as uranium and plutonium.The nuclides (or isotopes) thorium-232, uranium-235, and uranium-238 occur primordially, while trace quantities of actinium, protactinium, neptunium, and plutonium exist as a result of radioactive decay and (in the case of neptunium ...
Actinide chemistry. Plutonium is a transuranic radioactive chemical element, an actinide metal. Actinide chemistry (or actinoid chemistry) is one of the main branches of nuclear chemistry that investigates the processes and molecular systems of the actinides. The actinides derive their name from the group 3 element actinium.
Actinium-227 (half-life 21.77 years) occurs in all uranium ores, but in small quantities. One gram of uranium (in radioactive equilibrium) contains only 2 × 10 −10 gram of 227 Ac. [30] [57] Actinium-228 is a member of the radioactive thorium series formed by the decay of 228 Ra; [60] it is a β − emitter with a half
There are 34 known isotopes, from 203 Ac to 236 Ac, and 7 isomers. Three isotopes are found in nature, 225 Ac, 227 Ac and 228 Ac, as intermediate decay products of, respectively, 237 Np, 235 U, and 232 Th. 228 Ac and 225 Ac are extremely rare, so almost all natural actinium is 227 Ac. The most stable isotopes are 227 Ac with a half-life of 21. ...
Marguerite Catherine Perey (19 October 1909 – 13 May 1975) was a French physicist and a student of Marie Curie. In 1939, Perey discovered the element francium by purifying samples of lanthanum that contained actinium. In 1962, she was the first woman to be elected to the French Académie des Sciences, an honor denied to her mentor Curie.
Actinium compounds are compounds containing the element actinium (Ac). Due to actinium's intense radioactivity, only a limited number of actinium compounds are known. These include: AcF 3, AcCl 3, AcBr 3, AcOF, AcOCl, AcOBr, Ac 2 S 3, Ac 2 O 3, AcPO 4 and Ac (NO 3) 3. Except for AcPO 4, they are all similar to the corresponding lanthanum compounds.
72400-000. Area code. +55 61. Website. www.gama.df.gov.br. Gama ( Portuguese pronunciation: [ˈɡɐ.ma]) is an administrative region in the Federal District in Brazil. It is bordered by Recanto das Emas to the north, Riacho Fundo II and Park Way to the northeast, and Santa Maria to the east.