Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Because of its high chemical reactivity barium is never found in nature as a free element.
Three reasons Barium stands out
- 1
This element has a slight golden hue when pure. Used in x-ray imaging.
- 2
Patients swallow a thick suspension of its sulfate compound so doctors can image the digestive tract with X-rays.
- 3
Its salts burn a vivid green colour, making them useful in fireworks and signal flares.
A heavy metal that reveals the digestive tract
Barium metal is dangerously reactive, but insoluble barium sulfate can pass through the body with little absorption. Its opacity to X-rays outlines the digestive system during medical imaging. Other barium compounds color fireworks green and help drilling fluids counter pressure deep underground.