Even though the element has been known for centuries, credit for the discovery was given to Albertos Magnus. There are two forms of arsenic that you might encounter in chemistry. There is a yellow form and a gray form that most people are familiar with. The gray form is semi-metallic (you might see the term metalloid) and has physical traits that are crystalline and brittle.
Most people think of poison when they think of the element arsenic. When present in high concentrations, arsenic can kill you instantly. When arsenic is present in very small amounts (soils or water supply), it can kill and poison you over many years.
Where else can you find arsenic?
Fireworks
We'll start with an exciting use for arsenic. You'll find trace amounts of this element in fireworks and pyrotechnics for an added boost of color.
Lasers
Another upbeat use for arsenic. Gallium arsenide is used in certain lasers. It is able to be charged and then release the light that becomes the laser.
Minerals
Arsenic is all around you, but it's not in a pure form. Arsenic is a part of many minerals and rocks. You may have heard of Orpiment that is the molecule arsenic sulfide.
Poisons
We've mentioned it on every page. Arsenic is a nasty poison that will kill almost any living organism. You will find it in insecticides, rat poison, and even has been used to murder people. It's nasty stuff and if you ever have to handle poisons, always use gloves. Even small amounts of the element are dangerous over time.