Atomic Number: 89

Name: Actinium

Atomic symbol: Ac

Atomic Weight: 227.0278

Electron configuration: 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰6s²6p⁶6d¹7s²

Melting Point: 1050^oC

Boiling Point: 3200^oC

Ionic radius: 1.18 angstroms (+3)