barium

Barium is a chemical element with the symbol Ba and atomic number 56. It is a soft, silvery-white, highly reactive metal that is found in nature as the mineral barite. Barium is a heavy metal that is toxic in high doses.

Barium is used in a variety of applications, including:

• Medical imaging: Barium sulfate is used as a contrast agent in X-rays and CT scans.
• Fireworks: Barium salts are used to create the green colour in fireworks.
• Glassmaking: Barium is added to glass to make it opaque and to improve its chemical resistance.
• Batteries: Barium is used in some types of batteries.

Barium is a relatively rare element, and it is not found in high concentrations in the Earth's crust. However, it is a relatively abundant element in the universe, and it is thought to be present in the sun and other stars.

Barium is used in X-rays and CT scans to highlight the digestive tract.