atomic_number: 91
symbol: Pa
name: Protactinium
category: Actinide
category_label: Actinide
period: 7
group: null
group_label: Actinide
block: f
grid_row: 10
grid_col: 6
phase: solid
lab_made: false
radioactive_marker: false
is_radioactive: true
atomic_mass: '231.036'
atomic_mass_value: 231.036
atomic_mass_most_stable_isotope: false
oxidation_states: '*5* 4'
oxidation_states_parsed:
- state: '5'
  common: true
- state: '4'
  common: false
ionization_energy: '5.89'
ionization_energy_ev: 5.89
electron_configuration: '[Rn] 5f^{2}6d^{1}7s^{2}'
electron_configuration_formatted: '[Rn]5f²6d¹7s²'
electron_configuration_html: '[Rn]5f<sup>2</sup>6d<sup>1</sup>7s<sup>2</sup>'
atomic_radius: '2.43'
atomic_radius_angstrom: 2.43
electron_affinity: U
electron_affinity_ev: null
rsc_url: https://www.rsc.org/periodic-table/element/91/protactinium