Themes > Science > Chemistry > General Chemistry > Elements > Online Interactive Periodic Table of the Elements > Arsenic

Name: Arsenic
Symbol: As
Atomic Number: 33
Atomic Mass: 74.9216 amu
Melting Point: 817.0 °C (1090.15 °K, 1502.6 °F)
Boiling Point: 613.0 °C (886.15 °K, 1135.4 °F)
Number of Protons/Electrons: 33
Number of Neutrons: 42
Crystal Structure: Rhombohedral
Density @ 293 K: 5.72 g/cm3
Color: Gray

Atomic Structure
[Bohr Model of Arsenic]  
Number of Energy Levels: 4

    First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 5

Isotopes

Isotope Half Life
As-71 2.7 days
As-72 26.0 hours
As-73 80.3 days
As-74 17.8 days
As-75 Stable
As-76 26.3 hours
As-77 39.0 hours
As-79 9.0 minutes
 

Facts

Date of Discovery: Known to the ancients
Discoverer: Unknown
Name Origin: From the Greek word arsenikos and the Latin word arsenicum
Uses: Poison, conducts electricity, semiconductors
Obtained From: mispickel


Information provided by: http://www.chemicalelements.com