Fránsíọ̀m

Francium, ₈₇Fr

Francium
Pípè	/ˈfrænsiəm/ ​(FRAN-see-əm)
Ìhànsójú	metallic
nọ́mbà ìsújọ	[223]
Francium ní orí tábìlì àyè
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Cs ↑ Fr ↓ Uue radon ← francium → radium
Nọ́mbà átọ̀mù (Z)	87
Ẹgbẹ́	group 1: H and alkali metals
Àyè	àyè 7
Àdìpọ̀	Àdìpọ̀-s
Ẹ̀ka ẹ́límẹ́ntì	Alkali metal
Ìtò ẹ̀lẹ́ktrọ́nù	[Rn] 7s1
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan	2, 8, 18, 32, 18, 8, 1
Àwọn ohun ìní ara
Ìfarahàn at STP	solid
Ìgbà ìyọ́	? 300 K ​(? 27 °C, ​? 80 °F)
Ígbà ìhó	? 950 K ​(? 677 °C, ​? 1250 °F)
Kíki (near r.t.)	1.87 g/cm3
Heat of fusion	ca. 2 kJ/mol
Heat of	ca. 65 kJ/mol
pressure (extrapolated) P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 404 454 519 608 738 946
Atomic properties
Oxidation states	+1 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment
Electronegativity	Pauling scale: 0.7
Covalent radius	260 pm
Van der Waals radius	348 pm
Other properties
Natural occurrence	from decay
Crystal structure	​(bcc)
Thermal conductivity	15 W/(m·K)
Electrical resistivity	3 µ Ω·m
Magnetic ordering	Paramagnetic
CAS Number	7440-73-5
Main isotopes of francium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 221Fr syn 4.8 min α 6.457 217At 222Fr syn 14.2 min β– 2.033 222Ra 223Fr trace 22.00 min β– 1.149 223Ra α 5.430 219At

Fránsíọ̀m tabi Francium, mimo tele bi eka-caesium ati actinium K, je apilese kemika to ni ami-idamo Fr ati nomba atomu 87. O ni ikan ninu awon odionina tokerejulo larin gbogbo awon apilese ti a mo, bakanna ohun ni apilese aladanida keji tosowonjulo (leyin astatine). Fransiom je onide to je radioalagbara giga to n jera si astatine, radium, ati radon. Gege bi onide alkali, o ni agbara elektroni kan.

Francium je wiwari latowo Marguerite Perey ni Fransi (nibi ti apilese yi ti ri oruko) ni 1939. Ohun ni apilese togbeyin ti o je wiwari ninu adanida, kanran jije sisopapo. Lode yara ise-idanwo, francium sowon gidigidi, iye ipase je wiwari ninu alumoni aladalu uranium ati thorium, nibi ti isotopu francium-223 ti n je didasile to si n je jijera bibaun. Iye to kere bi 20–30 g (ounce kan) lowa nigba yiowu kakiri inu igbele Aye; awon isotopu yioku je alasopapo yanyan. Iye titobijulo ti o je kikojo lai isotopu yiowu ni isupo bi awon atomu 10,000 (ti francium-210) ti won je didasaye gege bi efuufu tutugidi ni Stony Brook ni 1997.