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Iodine (I): Fun Facts and Information About the Element

What is the symbol? I
What is the atomic number? 53
What is the atomic weight? 126.9045
What is the melting point in Celsius? 114
What is the boiling point in Celsius? 184
What is the density (g/cm3)? 4.93
What year was it discovered? 1811
Who discovered the element? Barnard Courtois
What group is the element in? 17
What is the electron configuration? [Kr] 4d10 5s2 5p5
What is the ionization energy? 10.4513
What element category is it in? Alkaline earth metals

Where is Iodine Found?

Ultrapure iodine can be obtained from the reaction of potassium iodide with copper sulfate. Several other methods of isolating the element are known.

Where is Iodine Used For?

Iodine compounds are important in organic chemistry and very useful in medicine. Iodides, and thyroxine which contains iodine, are used internally in medicine, and as a solution of KI and iodine in alcohol is used for external wounds. Potassiumiodide finds use in photography.