Iodine

Position of iodine in the periodic table.

Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid and boils to a violet gas. The element was named after the Ancient Greek Ιώδης 'violet-coloured'. It is the least abundant of the stable halogens. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities.

Uses

Due to its high atomic number and ease of attachment to organic compounds, it has also found favour as a non-toxic radiocontrast material. Because of the specificity of its uptake by the human body, radioactive isotopes of iodine can also be used to treat thyroid cancer. Iodine is also used as a catalyst in the industrial production of acetic acid and some polymers.

See also

• Carbon
• Chlorine
• Helium
• Hydrogen
• Nitrogen
• Oxygen
• Phosphorus
• Sulfur
• Chemical elements

References

This article uses material from the Wikipedia article Iodine, which is released under the Creative Commons Attribution-ShareAlike 3.0 Unported License (view authors).