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51Sb121.760
Metalloidp-block

Antimony

Element 51 on the periodic table, symbol Sb, group 15, period 5.

Antimony is a chemical element with symbol Sb (from Latin: stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient times and were used for cosmetics; metallic antimony was also known, but it was erroneously identified as lead upon its discovery.

Appearance: silvery lustrous gray

Properties

Atomic Number
51
Atomic Mass
121.7601 u
Group
15
Period
5
Block
p-block
Category
Metalloid
State at 25 °C
Solid
Melting Point
903.8 K · 630.6 °C
Boiling Point
1,908 K · 1,634.9 °C
Density
6.697 g/cm³
Atomic Radius
145 pm
Electronegativity
2.05
Oxidation States
-3, +3, +5
Abundance in Crust
0.2 mg/kg
Discovered
Known since antiquity
Discovered By
No individual credited

Electron Configuration

[Kr] 4d10 5s2 5p3

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p3

Ionisation Energies (kJ/mol)

  1. 1. 834
  2. 2. 1,594.9
  3. 3. 2,440
  4. 4. 4,260
  5. 5. 5,400
  6. 6. 10,400

Elements near Antimony

Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.

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