Ράδιο

88
Ra
Ομάδα
2
Περίοδος
7
Τομέας
s
Πρωτονίων
Electrons
Νετρονίων
88
88
138
General Properties
Ατομικός Αριθμός
88
Ατομικό βάρος
[226]
Mass Number
226
Κατηγορία
Αλκαλικές γαίες
Χρώμα
Silver
Radioactive
Ναι
From the Latin word radius meaning ray
Κρυσταλλικό σύστημα
Body Centered Cubic
Ιστορία
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.
Electrons per shell
2, 8, 18, 32, 18, 8, 2
Ηλεκτρονική διαμόρφωση
[Rn] 7s2
Ra
Radium imparts a carmine red color to a flame
Physical Properties
Phase
Στερεά
Πυκνότητα
5,5 g/cm3
Σημείο τήξης
973,15 K | 700 °C | 1292 °F
Σημείο βρασμού
2010,15 K | 1737 °C | 3158,6 °F
Heat of Fusion
8 kJ/mol
Heat of Vaporization
125 kJ/mol
Ειδική θερμοχωρητικότητα
-
Abundance in Earth's crust
9,9×10-12%
Abundance in Universe
n/a
Pierre
Image Credits: hp.ujf.cas.cz
Pierre and Marie Curie in the laboratory
CAS Number
7440-14-4
PubChem CID Number
6328144
Atomic Properties
Ατομική ακτίνα
-
Ομοιοπολική ακτίνα
221 pm
Ηλεκτραρνητικότητα
0,9 (Κλίμακα Pauling)
Ionization Potential
5,2784 eV
Atomic Volume
45,20 cm3/mol
Θερμική αγωγιμότητα
0,186 W/cm·K
Oxidation States
2
Applications
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 is highly radioactive and carcinogenic
Ισότοπα
Stable Isotopes
-
Unstable Isotopes
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