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Element 79 - Gold (Au)
From the old English word
geolo
, or yellow; symbol Au from its Latin name
aurum
; prehistoric; the most malleable metal. It is used for money, jewelery, dental work, and some electronics.
Properties
Atomic Number
:
79
Atomic Weight
:
196.9665
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
10
4f
14
5s
2
5p
6
5d
10
6s
1
Oxidation States
(Bold most stable):
+3
, +1
Boiling Point
(K):
3130
Melting Point (K):
1337.58
Density
(at 300K -- g/cm
3
):
19.3
Atomic Volume (at 300K -- cm
3
/mol)
10.20
Number of stable
isotopes
:
1
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
195 -- 183 days -- orbital
electron capture
196 -- 6.18 days --
positron
emission, orbital
electron capture
,
beta particle
(
electron
) emission
198 -- 2.696 days --
beta particle
(
electron
) emission
199 -- 3.15 days --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.34
Atomic Radius (Å):
1.46
First
Ionization Potential
(V):
9.225
Electronegativity
(Pauling's):
2.54
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.128
Heat of Vaporization (kJ/mol):
324.43
Heat of Fusion (kJ/mol):
12.36
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
48.8
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
317
Crystal Structure:
Cubic, face centered
Acid
-
Base
Properties:
Amphoteric