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Element 35 - Bromine (Br)
From
bromos
, or stench; discovered 1826; a red, caustic, fuming liquid with a foul smell. Bromine is an effective disinfectant. Among its compounds are the bromides, used in nerve sedatives and in petrol anti-knock compounds that make car engines run smoothly.
Properties
Atomic Number
:
35
Atomic Weight
:
79.904
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
5
Oxidation States
(Bold most stable):
-1
, +1, +5, +7
Boiling Point
(K):
331.85
Melting Point (K):
265.95
Density
(at 300K -- g/cm
3
):
3.12
Atomic Volume (at 300K -- cm
3
/mol)
23.5
Number of stable
isotopes
:
2
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
82 -- 35.34 hours --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.14
Atomic Radius (Å):
1.12
First
Ionization Potential
(V):
11.814
Electronegativity
(Pauling's):
2.96
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.226
Heat of Vaporization (kJ/mol):
14.725
Heat of Fusion (kJ/mol):
5.286
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
10
-16
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
0.122
Crystal Structure:
Orthorhombic
Acid
-
Base
Properties:
Very acidic