Ion At^- (Minus one)

Symbol	At-
Number	85
Atomic weight	Нестабилен
Latin name	Astatum
English name	Astatine

How to build an electronic configuration by yourself? See link

Electronic configuration of of Astatine

At: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁵ → At^-:1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²4f¹⁴5d¹⁰6p⁶

Same electronic configuration has an ion of Astatine -1 and Bi^-3, Po^-2, Rn, Fr⁺¹, Ra⁺², Ac⁺³, Th⁺⁴, Pa⁺⁵, U⁺⁶, Np⁺⁷

The order of filling the shells with electrons of Astatine (At^-): 1s → 2s → 2p → 3s → 3p → 4s → 3d → 4p → 5s → 4d → 5p → 6s → 4f → 5d → 6p → 7s → 5f → 6d → 7p.

On the sub level ‘s’ there might be 2 electrons at most, on ‘p’ - up to 6, on ‘d’ - up to 10 and up to 14 on ‘f’

Astatine has 85 electrons, let's fill electronic layers in described order:

2 electrons on 1s-sub level

2 electrons on 2s-sub level

6 electrons on 2p-sub level

2 electrons on 3s-sub level

6 electrons on 3p-sub level

2 electrons on 4s-sub level

10 electrons on 3d-sub level

6 electrons on 4p-sub level

2 electrons on 5s-sub level

10 electrons on 4d-sub level

6 electrons on 5p-sub level

2 electrons on 6s-sub level

14 electrons on 4f-sub level

10 electrons on 5d-sub level

6 electrons on 6p-sub level

Oxidation state of Astatine

Atoms of Astatine in compounds have an oxidation state of 7, 5, 3, 1, -1.

The oxidation state is the conditional charge of an atom in a compound: the bond in a molecule between atoms is based on the sharing of electrons, thus, if the atom’s charge virtually increases, then the oxidation state is negative (electrons carry a negative charge), if the charge decreases, then the oxidation state is positive.

Oxidation state of an ion At^- = -1

Ions of Astatine

Valence of At^-

Atoms of Astatine in compounds have valence VII, V, III, I.

Valence of Astatine is an ability of an atom At to build chemical bounds. The valence is based on electronic configuration of atom: electrons participated in chemical bounds are known as valence electrons. In general the valence is:

The number of possible chemical bounds with other atoms

The valence has no sign.

Quantum numbers At ^1-

Quantum numbers are defined by the last electron in configuration, for an ion At these numbers are N = 6, L = 1, M_l = 1, M_s = -½

Filling an electronic configuration (gif):



Result: