Radium

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Radium,  88Ra
Radium226.jpg
General properties
Name, seembol radium, Ra
Appearance sillery white metallic
Pronunciation /ˈrdiəm/
RAY-dee-əm
Radium in the periodic cairt
Hydrogen (diatomic nonmetal)
Helium (noble gas)
Lithium (alkali metal)
Beryllium (alkaline yird metal)
Boron (metalloid)
Carbon (polyatomic nonmetal)
Nitrogen (diatomic nonmetal)
Oxygen (diatomic nonmetal)
Fluorine (diatomic nonmetal)
Neon (noble gas)
Sodium (alkali metal)
Magnesium (alkaline yird metal)
Aluminium (post-transeetion metal)
Silicon (metalloid)
Phosphorus (polyatomic nonmetal)
Sulfur (polyatomic nonmetal)
Chlorine (diatomic nonmetal)
Argon (noble gas)
Potassium (alkali metal)
Calcium (alkaline yird metal)
Scandium (transeetion metal)
Titanium (transeetion metal)
Vanadium (transeetion metal)
Chromium (transeetion metal)
Manganese (transeetion metal)
Airn (transeetion metal)
Cobalt (transeetion metal)
Nickel (transeetion metal)
Capper (transeetion metal)
Zinc (transeetion metal)
Gallium (post-transeetion metal)
Germanium (metalloid)
Arsenic (metalloid)
Selenium (polyatomic nonmetal)
Bromine (diatomic nonmetal)
Krypton (noble gas)
Rubidium (alkali metal)
Strontium (alkaline yird metal)
Yttrium (transeetion metal)
Zirconium (transeetion metal)
Niobium (transeetion metal)
Molybdenum (transeetion metal)
Technetium (transeetion metal)
Ruthenium (transeetion metal)
Rhodium (transeetion metal)
Palladium (transeetion metal)
Siller (transeetion metal)
Cadmium (transeetion metal)
Indium (post-transeetion metal)
Tin (post-transeetion metal)
Antimony (metalloid)
Tellurium (metalloid)
Iodine (diatomic nonmetal)
Xenon (noble gas)
Caesium (alkali metal)
Barium (alkaline yird metal)
Lanthanum (lanthanide)
Cerium (lanthanide)
Praseodymium (lanthanide)
Neodymium (lanthanide)
Promethium (lanthanide)
Samarium (lanthanide)
Europium (lanthanide)
Gadolinium (lanthanide)
Terbium (lanthanide)
Dysprosium (lanthanide)
Holmium (lanthanide)
Erbium (lanthanide)
Thulium (lanthanide)
Ytterbium (lanthanide)
Lutetium (lanthanide)
Hafnium (transeetion metal)
Tantalum (transeetion metal)
Tungsten (transeetion metal)
Rhenium (transeetion metal)
Osmium (transeetion metal)
Iridium (transeetion metal)
Platinum (transeetion metal)
Gold (transeetion metal)
Mercur (transeetion metal)
Thallium (post-transeetion metal)
Leid (post-transeetion metal)
Bismuth (post-transeetion metal)
Polonium (post-transeetion metal)
Astatine (metalloid)
Radon (noble gas)
Francium (alkali metal)
Radium (alkaline yird metal)
Actinium (actinide)
Thorium (actinide)
Protactinium (actinide)
Uranium (actinide)
Neptunium (actinide)
Plutonium (actinide)
Americium (actinide)
Curium (actinide)
Berkelium (actinide)
Californium (actinide)
Einsteinium (actinide)
Fermium (actinide)
Mendelevium (actinide)
Nobelium (actinide)
Lawrencium (actinide)
Rutherfordium (transeetion metal)
Dubnium (transeetion metal)
Seaborgium (transeetion metal)
Bohrium (transeetion metal)
Hassium (transeetion metal)
Meitnerium (unkent chemical properties)
Darmstadtium (unkent chemical properties)
Roentgenium (unkent chemical properties)
Copernicium (transeetion metal)
Ununtrium (unkent chemical properties)
Flerovium (post-transeetion metal)
Ununpentium (unkent chemical properties)
Livermorium (unkent chemical properties)
Ununseptium (unkent chemical properties)
Ununoctium (unkent chemical properties)
Ba

Ra

(Ubn)
franciumradiumactinium
Atomic nummer (Z) 88
Group, block group 2 (alkaline yird metals), s-block
Period period 7
Element category   alkaline yird metal
Staundart atomic wicht (Ar) (226)
Electron configuration [Rn] 7s2
per shell
2, 8, 18, 32, 18, 8, 2
Pheesical properties
Phase solid
Meltin pynt 1233 K ​(960 °C, ​1760 °F) (disputed)
Bylin pynt 2010 K ​(1737 °C, ​3159 °F)
Density near r.t. 5.5 g/cm3
Heat o fusion 8.5 kJ/mol
Heat o vapourisation 113 kJ/mol
vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 819 906 1037 1209 1446 1799
Atomic properties
Oxidation states 2 ​(expectit tae hae a strangly basic oxide)
Electronegativity Pauling scale: 0.9
Ionisation energies 1st: 509.3 kJ/mol
2nt: 979.0 kJ/mol
Covalent radius 221±2 pm
Van der Waals radius 283 pm
Miscellanea
Creestal structur ​body-centred cubic
[[File:body-centred cubic|50px|alt=Body-centred cubic crystal structur for radium|Body-centred cubic crystal structur for radium]]
Thermal conductivity 18.6 W/(m·K)
Electrical resistivity 1 µΩ·m (at 20 °C)
Magnetic orderin nonmagnetic
CAS Nummer 7440-14-4
History
Diskivery Pierre Curie an Marie Curie (1898)
First isolation Marie Curie (1910)
Maist stable isotopes o radium
iso NA hauf-life DM DE (MeV) DP
223Ra trace 11.43 d α 5.99 219Rn
224Ra trace 3.6319 d α 5.789 220Rn
225Ra trace 14.9 d β 0.356 225Ac
226Ra trace 1600 y α 4.871 222Rn
228Ra trace 5.75 y β 0.046 228Ac
· references

Radium is a chemical element wi seembol Ra an atomic nummer 88.