Astatine 85

Atomic No. Order:

Alphabetic Order:

Periodic Table

2, 8, 18, 32,

18, 7

F
9

Cl
17

Br
35

I
53

At
85

Uus
117

Uhs
167

Bus
217

Astatine

Symbol

Atomic Number

Group

halogens

Relative Atomic Mass
¹²C = 12.0000

[ 210 ]
209.9871
8.1(4) hour

Significant Atomic Mass

217
Neutrons 132

Isotop

211
210.9875
7.21(1) hour

Atomic Radius pm

140

First Ionisation Energy
kJ mol ^-1

930

Ionization energy (eV)

Electronegativity

2.2

Density kg m ^-3

Molar Volume cm ³

Thermal Conductivity
W m ^-1 K ^-1

1.7 [300 K]

Melting Point K

575 (est.)

Boiling Point K

610 (est.)

Number of Isotopes

Inner + outer Shells

Inner + outer Orbitals

Filling Orbital

6p ⁵

Ground State Electron
Configuration

[Xe]

5d ¹⁰

6p ⁵

Ground State Electron
Configuration with
free Orbitals (n=1)

0, 0, 0, 0, 0, 1

Ground State Electron Configuration with compressed Orbitals (n=96)

0,0,0,0,32,64

0, 0, 0, 0, 32, 64

Singularity

182

	s	p		d	f	g	h	i	j
1	2
2	2	6
3	2	6		10
4	2	6		10	14
5	2	6		10	14	18
6	2	5	1	10	14	18	22
7
8

Term Symbol

²P^º_3/2

Discovery

Discovered by D.R. Corson, K.R. Mackenzie and E. Segré (Berkeley, USA) in 1940

Name Derived From

Greek astatos meaning 'unstable'

APSIDIUM ©	Created:	2002-08-12	085.pdf
	Page update:	2005-01-18	085.pdf