Share to: share facebook share twitter share wa share telegram print page

Polónium

Polónium
(polonium)
bizmut ← polónium → astát
Te

Po

Lv
84
Periodická tabuľka
6. perióda, 16. skupina, blok p
polokovy
Vzhľad
striebristý kov
Atómové vlastnosti
Atómová hmotnosť (209) g·mol−1
Elektrónová konfigurácia [Xe] 4f14 5d10 6s2 6p4
Atómový polomer 168 pm
Kovalentný polomer 140 pm
Van der Waalsov pol. 197 pm
Chemické vlastnosti
Elektronegativita 2,0 (podľa Paulinga)
Oxidačné číslo(a) -II, II, IV, VI
Fyzikálne vlastnosti (za norm. podmienok)
Skupenstvo pevné
Hustota 9,196 kg·dm−3
Teplota topenia 527 K (253,85 °C)
Teplota varu 1 235 K (961,85 °C)
Sk. teplo topenia 13 kJ·mol−1
Sk. teplo varu 102,91 kJ·mol−1
Tepelná kapacita 26,4 J·mol−1·K−1
Tlak pary
p(Pa) 1 10 100 1 k 10 k 100 k
pri T(K) (846) 1 003 1 236
Iné
Kryštálová sústava kubická
Elektrický odpor 0,40 nΩ·m
Tep. vodivosť 20 W·m−1·K−1
Tep. rozťažnosť 23,5 µm·m−1·K−1
Reg. číslo CAS 7440-08-6
Izotop(y) (vybrané)
Izotop Výskyt t1/2 Rr Er (MeV) Pr
 208Po synt. 2,898 r. α 5,215 204Pb
synt.   ε, β+ 1,401 208Bi
 209Po synt. 103 r. α 4,979 205Pb
synt.   ε, β+ 1,893 209Bi
 210Po stopy 138,376 d. α 5,307 206Pb
 Commons ponúka multimediálny obsah na tému polónium.

Polónium (polonium) je chemický prvok v Periodickej tabuľke prvkov, ktorý má značku Po a protónové číslo 84. Polónium je zriedkavý rádioaktívny prvok, vyskytujúci sa v uránovej rude.

Polónium objavila Maria Curieová-Skłodowská v roku 1898 pri skúmaní rádioaktivity v jáchymovskom smolinci a pomenovala ho na počesť svojej vlasti Poľska. Na získanie 250 mg Po bolo potrebné spracovať vyše 1 000 000 kg smolinca.

Dmitrij Ivanovič Mendelejev predpovedal takýto prvok 38 rokov pred jeho objavením. Polónium je rádioaktívny kov s polčasom rozpadu 138,38 dňa. Vzniká ako člen rádioaktívnych rozpadových radov. Polónium je alfa žiarič.

Vzhľadom na to, že Po má krátky polčas rozpadu, poskytuje značné množstvo energie (140 W na 1 g kovu) a odtiaľ pramení jeho samoohrievacia schopnosť, ktorú majú aj jeho zlúčeniny.

Využitie

Polónium sa používa ako ľahký svetelný zdroj alebo ako spontánny a spoľahlivý kompaktný zdroj termoelektrického napätia pre kozmické sondy a lunárne stanice.

Otrava

V roku 2006 zomrel na otravu polóniom 210 Alexandr Litvinenko a z vraždy bol obvinený ruský ex-špión Andrej Lugovoj.[1] Britský fyzik Norman Dombey oznámil vyšetrovateľom, že Litvinenko zomrel po dávke 26,5 mikrogramu polónia.[2]

Referencie

  1. Pitva Litvinenka bola život ohrozujúca, tvrdí britský lekár
  2. Polónium, ktoré zabilo Litvinenka, vraj mohlo vyrobiť len Rusko

Iné projekty

  • Spolupracuj na Commons Commons ponúka multimediálne súbory na tému polónium

Read other articles:

يفتقر محتوى هذه المقالة إلى الاستشهاد بمصادر. فضلاً، ساهم في تطوير هذه المقالة من خلال إضافة مصادر موثوق بها. أي معلومات غير موثقة يمكن التشكيك بها وإزالتها. (ديسمبر 2018) بطولة أمريكا المفتوحة 2006 - الزوجي المختلط جزء من أمريكا المفتوحة 2006  البلد الولايات المتحدة  التاري...

Ngày Dân số Thế giớiMật độ dân số theo quốc gia năm 2007Tên chính thứcWorld Population DayTên gọi khácWPDCử hành bởiThành viên Liên Hợp QuốcNgày11 tháng BảyHoạt độngLiên Hợp QuốcCử hànhNâng cao nhận thức về dân số toàn cầuTần suấthàng năm Mật độ dân số theo quốc gia năm 2007 Ngày Dân số Thế giới là một sự kiện thường niên diễn ra vào ngày 11 tháng 7 hàng năm, nhằm nâng cao nhận...

Танець{{{назва}}} Картина відомого російського художника Василя Верещагіна «Лезгінський танець», який після відвідування Південного Дагестану і Єлізаветпільскої губернії написав цю картину, спостерігаючи за звичаями і традиціями лезгінів. (1867 р.) Фотографія «Лезгини,...

Seine Seligkeit Joseph I., Patriarch von Antiochien Patriarch Joseph I coat of arms Joseph I. SMSP, gebürtig Youssef Absi, (* 20. Juni 1946 in Damaskus) ist Patriarch von Antiochien und dem Ganzen Orient, von Alexandrien und von Jerusalem und Oberhaupt der Melkitischen Griechisch-Katholischen Kirche, welche mit der römisch-katholischen Kirche uniert ist. Inhaltsverzeichnis 1 Kirchliche Laufbahn 2 Aktivitäten 3 Zum Nahen Osten 4 Weblinks 5 Einzelnachweise Kirchliche Laufbahn Joseph Absi emp...

У Вікіпедії є статті про інші значення цього терміна: Любашівка (значення). Селище Любашівка Герб Любашівки Прапор Любашівки Центральна площа містечкаЦентральна площа містечка Країна  Україна Область Одеська область Район  Подільський район Громада Любашівська...

فاميلي غاي من اليمين: ميغ، كريس، ستوي، بيتر، لويس، وبراين النوع رسوم متحركةكوميديا الموضوع عائلة مختلة  تأليف سيث ماكفارلن إخراج سيث ماكفارلنديفيد زوكرمان بطولة سيث ماكفارلنآليكس بورستينسيث قرينميلا كونيسمايك هنري البلد الولايات المتحدة[1]  لغة العمل الإنجليزي...

العلاقات الأرجنتينية السعودية الأرجنتين السعودية   الأرجنتين   السعودية تعديل مصدري - تعديل   العلاقات الأرجنتينية السعودية هي العلاقات الثنائية التي تجمع بين الأرجنتين والسعودية.[1][2][3][4][5] مقارنة بين البلدين هذه مقارنة عامة ومرجعية للدول

River in Maharashtra, IndiaBindusara RiverLocationCountryIndiaStateMaharashtraDistrictBeedPhysical characteristicsSource  • locationBalaghat Range, India Length40 km (25 mi) Bindusara (also called Bendsura) is a small river situated in the district of Beed in Maharashtra state of India. It is a tributary river of Sindphana and a sub-tributary of Godavari river. Bendsura dam overflowing in monsoon. Balaghat Range can be seen in the background. Bindusara orig...

Bangladeshi politician SM Rezaul Karimশ ম রেজাউল করিমMinister of Fisheries and LivestockIncumbentAssumed office 13 February 2020Preceded byNarayon Chandra ChandaMinister of Housing and Public WorksIn office7 January 2019 – 13 February 2020Preceded byMosharraf HossainSucceeded byVacantMember of Parliamentfor Pirojpur-1IncumbentAssumed office 30 January 2019Preceded byAKMA Awal Personal detailsBorn (1962-02-18) February 18, 1962 (age 61)[1]...

Classical diffusion is a key concept in fusion power and other fields where a plasma is confined by a magnetic field within a vessel. It considers collisions between ions in the plasma that causes the particles to move to different paths and eventually leave the confinement volume and strike the sides of the vessel. The rate of diffusion scales with 1/B2, where B is the magnetic field strength, implies that confinement times can be greatly improved with small increases in field strength. In p...

1993 single by Manic Street Preachers Roses in the HospitalSingle by Manic Street Preachersfrom the album Gold Against the Soul Released20 September 1993 (1993-09-20)Genre Funk[1] funk rock[2] Baggy Length5:02LabelEpicSongwriter(s) Richey Edwards Nicky Wire James Dean Bradfield Sean Moore Producer(s)Dave EringaManic Street Preachers singles chronology La Tristesse Durera (Scream to a Sigh) (1993) Roses in the Hospital (1993) Life Becoming a Landslide (1994) Rose...

Public university in Ann Arbor, Michigan This article is about the main campus located in Ann Arbor, Michigan. For other uses, see University of Michigan (disambiguation). University of MichiganLatin: Universitas MichiganiaFormer namesCatholepistemiad (1817–1821)MottoLatin: Artes, Scientia, VeritasMotto in EnglishArts, Knowledge, TruthTypePublic research universityEstablishedAugust 26, 1817; 206 years ago (1817-08-26)[1]AccreditationHLCAcademic affiliationsAAU...

Southampton F.C. 1992–93 football seasonSouthampton F.C.1992–93 seasonChairmanGuy AskhamManagerIan BranfootStadiumThe DellFA Premier League18thFA CupThird RoundLeague CupThird RoundTop goalscorerLeague: Matthew Le Tissier (15)All: Matthew Le Tissier (18)Highest home attendance19,654 vs Tottenham Hotspur (15 August 1992)Lowest home attendanceLeague:10,827 vs Oldham Athletic(31 October 1992)Overall:6,764 vs Gillingham(7 October 1992)Average home league attendanceLeague: 15,148Overall: 14,51...

Railway station in Lambeth, South London, England Herne Hill Herne HillLocation of Herne Hill in Greater LondonLocationHerne HillLocal authorityLondon Borough of LambethGrid referenceTQ319744Managed bySoutheasternStation codeHNHDfT categoryC2Number of platforms4AccessibleYes[1]Fare zone2 and 3National Rail annual entry and exit2017–18 2.952 million[2]– interchange  1.734 million[2]2018–19 2.888 million[2]– interchange  1.537 million[2]...

Hypothetical racial grouping Race History Historical concepts Biblical terminology for race Society Color terminology Race relations Racialization Racism (scientific racism) Racial equality Racial politics Sociology of race Race and... Crime (United Kingdom, United States) Genetics Health (United States) Horror films Intelligence (history) Neuroscience Sexuality Society Sports Video games By location Race and ethnicity in censuses Brazil Colombia Latin America United States Related topics Col...

1971 single by Dennis Coffey and the Detroit Guitar BandScorpioSingle by Dennis Coffey and the Detroit Guitar Bandfrom the album Evolution B-sideSad AngelReleasedSeptember 1971[1]GenreR&B[2]Length3:59LabelSussexSongwriter(s)Dennis CoffeyProducer(s)Mike TheodoreDennis Coffey and the Detroit Guitar Band singles chronology It's Your Thing (1969) Scorpio (1971) Taurus (1972) Scorpio is a song by Dennis Coffey and the Detroit Guitar Band. It charted at number 6 on the Billboard...

American-Israeli religious leader For other people named Yisroel Friedman, see Yisroel Friedman (disambiguation). RabbiYisroel Moshe Friedmanרב ישראל משה פרידמאן‎PersonalBornJuly 23, 1955Brooklyn, New YorkDiedAugust 10, 2020(2020-08-10) (aged 65)Ramat Gan, IsraelReligionJudaismSpouseSarah Friedman (née Feldman)ParentsRabbi Avraham Yaakov Friedman (father)Tziporah Feiga Friedman (mother)DenominationHasidic JudaismYahrtzeitכא אב תשפBuriedAugust 11, 2020Dynast...

Board game Advanced HeroQuestPublishersGames WorkshopPlayers1 to 5Playing timeca. 90 minutesChanceDice rolling Advanced HeroQuest is a board game published by Games Workshop in 1989, a sequel to HeroQuest. Description The original HeroQuest was an adventure board game created in 1989 by Milton Bradley in conjunction with the British company Games Workshop. Later the same year, Games Workshop released Advanced HeroQuest, a similar but more complex game. Changes from HeroQuest include more comp...

Experimento de accidente de Boeing 727 en 2012 El avión experimental mientras aún estaba en servicio para Champion AirFecha 2012 de abril del 27 10:00Causa Choque deliberado controlado a distancia contra el terrenoLugar Laguna Salada (Baja California)Coordenadas 32°22′N 115°40′O / 32.36, -115.66Origen Aeropuerto Internacional General Rodolfo Sánchez Taboada (IATA: MXL, ICAO: MMML)ImplicadoTipo Boeing 727Experimento de accidenteOperador Discovery ChannelRegistro XB-MNP...

Partido Socialista de AlbaniaPartia Socialiste e Shqipërisë Presidente Edi RamaPortavoz parlamentario Taulant Balla[1]​Fundación 5 de junio de 1991Precedido por Partido del Trabajo de AlbaniaEslogan Por la Albania que queremosIdeología Socialdemocracia[2]​Europeísmo[3]​Posición Centroizquierda[4]​[5]​Sede Sheshi Austria 4, 1001 TiranaPaís Albania AlbaniaColores      PúrpuraOrganizaciónjuvenil Juventud SocialistaAfiliación internacion...

Kembali kehalaman sebelumnya