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                    • ▸▸
                      • 🇬🇧 Astatine
                      • 🇨🇳 砈
                      • 🇳🇱 Astaat
                      • 🇫🇷 Astate
                      • 🇩🇪 Astat
                      • 🇮🇱 אסטטין
                      • 🇮🇹 Astato
                      • 🇯🇵 アスタチン
                      • 🇵🇹 Astato
                      • 🇷🇺 Астат
                      • 🇪🇸 Astato
                      • 🇸🇪 Astat

                      Astatine: the essentials

                      Astatine atoms have 85 electrons and the shell structure is 2.8.18.32.18.7. The ground state electronic configuration of neutral astatine is [Xe].4f14.5d10.6s2.6p5 and the term symbol of astatine is 2P3/2.

                      Astatine: description  

                      The longest-lived isotope, 210网络斗地主下载At, has a half-life of only 8.3 hours. There are about 20 isotopes known, all of which are radioactive. Astatine is a halogen and possibly accumulates in the thyroid like iodine.

                      astatine
                      This sample of uranite contains a vanishingly small amount of astatine. Image adapted with permission from 's (U. North Texas, USA) Walking Tour of the elements CD.

                      Astatine: physical properties

                      More physical properties...

                      Astatine: heat properties

                      More thermochemical properties...

                      Astatine: atom sizes

                      More atomc size properties...

                      Astatine: electronegativities

                      More electronegativity properties...

                      Astatine: orbital properties

                      More orbital properties...

                      Astatine: abundances

                      More geological data...

                      Astatine: crystal structure

                      At crystal structure
                      The solid state structure of astatine is: bcc (body-centred cubic).

                      More crystallographic data...

                      Astatine: biological data

                      网络斗地主下载Astatine has no biological role.

                      More biological data...

                      Astatine: uses

                      Uses...

                      Astatine: reactions

                      网络斗地主下载 Reactions of astatine as the element with air, water, halogens, acids, and bases where known.

                      View reactions of astatine...

                      Astatine: binary compounds

                      Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of astatine where known.

                      View binary compounds...

                      Astatine: compound properties

                      网络斗地主下载 Bond strengths; lattice energies of astatine halides, hydrides, oxides (where known); and reduction potentials where known.

                      View compound properties...

                      Astatine: history

                      Astatine was discovered by Dale Corson, MacKenzie, Segre in 1940 at California, USA. Origin of name: from the Greek word "astatos" meaning "unstable".

                      More history...

                      Astatine: isotopes

                      Isotope abundances of astatine
                      Isotope abundances of astatine with the most intense signal set to 100%.

                      More isotope and NMR data...

                      Astatine: isolation

                      Isolation: astatine is radioactive and essentially unavailable in nature. It is not possible to make other than in a nuclear reactor. Bombardment of the bismuth isotope 20983Bi with α-particles (helium nuclei, 42He) results in formation of shortlived astatine and neutrons. The bismuth target is cooled during irradiation to prevent the volatile astatine disappearing.

                      20983Bi + 42He → 21185At + 2 10n

                      The 211At isotope has a half life of just over 7 hours so it is necessary to work quickly with it! Available quantities are of the order of 0.001 mg.

                      Heating the bismuth target to 300-600°C under N2 results in a stream of the elemental astatine that can be collected on a cold glass finger.

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