33
Arsenic
Atomic Number33
Atomic Mass74.922 u
CategoryMetalloid
State at Room TempSolid
Year Discovered1250
About Arsenic
Famous as a historical poison. Arsenic trioxide was called inheritance powder. Currently used in semiconductors, lead-acid batteries, and wood preservatives. Naturally occurs in groundwater in many countries, causing health problems for millions. Arsenic-based drugs were the first effective treatment for syphilis. Some organisms use arsenic in their metabolism.
More Metalloids
5
Boron
Essential for plant growth and used in fiberglass. Boron nitride is harder than ...
14
Silicon
The second most abundant element in Earths crust after oxygen. The foundation of...
32
Germanium
A semiconductor used in early transistors before silicon became dominant. Still ...
51
Antimony
Used in ancient Egypt as kohl eye makeup. Flame retardant in plastics and textil...