Radiu
88
Ra
Grupă
2
Perioadă
7
Bloc
s
Protoni
Electroni
Neutroni
88
88
138
Proprietăți Generale
Număr atomic
88
Masă atomică
[226]
Numar de masa
226
Categorie
Metale alcalino-pământoase
Culoare
Argint
Radioactive
Da
Din cuvântul latin radius, însemnând rază
Structură cristalină
Corp Centrat Cubic
Istoric
Radium was discovered by Marie Curie and Pierre Curie in 1898.
They extracted the radium compound from a uraninite sample.
Radium was isolated in its metallic state by Marie Curie and André-Louis Debierne in 1910 through the electrolysis of radium chloride by using a mercury cathode and distilling in an atmosphere of hydrogen gas.
They extracted the radium compound from a uraninite sample.
Radium was isolated in its metallic state by Marie Curie and André-Louis Debierne in 1910 through the electrolysis of radium chloride by using a mercury cathode and distilling in an atmosphere of hydrogen gas.
Electroni pe nivelul de energie
2, 8, 18, 32, 18, 8, 2
Configurație electronică
[Rn] 7s2
Radium imparts a carmine red color to a flame
Proprietăți Fizice
Fază
Solid
Densitate
5,5 g/cm3
Punct de topire
973,15 K | 700 °C | 1292 °F
Punct de fierbere
2010,15 K | 1737 °C | 3158,6 °F
Energie de fuziune
8 kJ/mol
Energie de evaporare
125 kJ/mol
Căldură specifică
-
Abundența în scoarța Pământului
9,9×10-12%
Abundența în Univers
n/a
Numarul CAS
7440-14-4
Număr CID PubChem
6328144
Proprietăți Atomice
Rază atomică
-
Rază de covalență
221 pm
Electronegativitate
0,9 (Scara lui Pauling)
Potențial de ionizare
5,2784 eV
Volum molar
45,20 cm3/mol
Conductivitate termică
0,186 W/cm·K
Număr de oxidare
2
Aplicații
Radium was formerly used in self-luminous paints for watches, nuclear panels, aircraft switches, clocks, and instrument dials.
Radium chloride was used in medicine to produce radon gas which in turn was used as a cancer treatment.
The isotope 223Ra is currently under investigation for use in medicine as a cancer treatment of bone metastasis.
Radium chloride was used in medicine to produce radon gas which in turn was used as a cancer treatment.
The isotope 223Ra is currently under investigation for use in medicine as a cancer treatment of bone metastasis.
Radium is highly radioactive and carcinogenic
Izotopi
Izotopi stabili
-Izotopi instabili
202Ra, 203Ra, 204Ra, 205Ra, 206Ra, 207Ra, 208Ra, 209Ra, 210Ra, 211Ra, 212Ra, 213Ra, 214Ra, 215Ra, 216Ra, 217Ra, 218Ra, 219Ra, 220Ra, 221Ra, 222Ra, 223Ra, 224Ra, 225Ra, 226Ra, 227Ra, 228Ra, 229Ra, 230Ra, 231Ra, 232Ra, 233Ra, 234Ra