Radium

Radium is a chemical element with the symbol Ra and atomic number 88. It is a highly radioactive, silvery-white metal that glows in the dark. Radium was discovered in 1898 by Marie Curie and Pierre Curie. It is primarily used in radiation therapy for cancer treatment and in some types of luminous paints.

Overview

English Name:

Radium

Latin Name:

Radium

Year Discovered:

1898

Discovered By:

Marie Curie, Pierre Curie

Group:

Period:

Electrons:

CAS Number:

7440-14-4

Cost Per 100 Grams:

$1000

Atomic Properties

Electronic Configuration:

[Rn] 7s²

Ion Charge:

Ionisation Energies:

509 kJ/mol

Atomic Radius (Empirical):

215 pm

Atomic Radius (Calculated):

248 pm

Covalent Radius:

200 pm

Van Der Waals Radius:

248 pm

Ionisation Potential of An Atom:

5.5 eV

Electrons Per Layer:

2, 8, 18, 32, 18, 8, 2

Atomic Multiplicities Of The Gas:

Atomic Weight:

226

Oxidation States

Reactivity

Electron Affinity:

Not well defined

Valence:

Electronegativity:

1.9

Thermal Properties

Melting Point:

1050 °C

Boiling Point:

1413 °C

Critical Point:

Pressure: N/A

Temperature: N/A

Thermal Conductivity:

0.120 W/(m·K)

Heat Capacity:

Specific: 0.11 J/(g·K)

Molar: 26.4 J/(mol·K)

Thermal Coefficient:

0.0001

Enthalpy:

Fusion: 5.5 kJ/mol

Vaporisation: 120 kJ/mol

Atomization: 300 kJ/mol

Curie Temperature:

N/A

Neel Temperature:

N/A

Superconductivity Point:

N/A

Physical and Chemical Properties

State of matter (25° C/ 77°F):

Solid

Density:

Solid: 5.5 g/cm³

Molar Volume (Vmol):

41.0 cm³/mol

Speed of Sound (Vs):

Not applicable

Hardness:

N/A

Bulk Modulus (K):

Not available

Shear Modulus (G):

N/A

Young's Modulus (E):

N/A

Color:

Silvery-white

Brinell Hardness (MPa):

N/A

Liquid Density (Kg/m^3):

4.5 kg/m³

Hardness of Mohs:

N/A

Refractive Index:

N/A

Vickers Hardness (MPa):

N/A

Crystal Structure:

N/A

Electromagnetic Properties

Electrical Type:

Conductor

Resistivity:

10^-6 Ω·m

Magnetic Type:

Diamagnetic

Superconductivity:

Not applicable

Volume Magnetic Susceptibility:

-1.0 × 10^-9

Mass Magnetic Susceptibility:

-1.2 × 10^-9 m³/kg

Molar Mass Susceptibility:

-3.0 × 10^-8 m³/mol

Electrical Conductivity:

10^-6 S/m

Mass (γ_mass):

3.5 × 10^-25 kg

Mass (γ_mol):

3.5 × 10^-22 mol

Volume (γ_vol):

41.0 L

Grid Parameters

Crystal Structure:

N/A

Grid Parameters:

N/A

Attitude:

N/A

Debye Temperature:

N/A

Safety and Precautions

Signal Word:

Danger

Hazard Statements:

H300, H310, H330

Precautionary Statements:

P201, P202, P280, P308 + P313

RTECS Number:

Not available

Risk:

Flammability: Non-flammable
Health Risk: Highly toxic
Reactivity: Unstable
Specific Risk: Radioactive

Importance

Main sources:

Uranium and thorium ores

Main Usage:

Radiation therapy, luminous paints

Nuclear Properties

Radioactive:

Yes

Isotopes:

Ra-226, Ra-228

Neutron Cross Sectional:

0.1 barns

Half Life (s):

1600 years

Lifetime:

Stable

Prevalence

Universe:

0.0000000001%

Sun:

0.0000000001%

Oceans:

0.00000000001%

Humans:

0.000000000001%

Earth's Crust:

0.0000000001%

Meteorites:

0.0000000001%