Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced /iconˈaɪ. ɵdaɪn/ -o-dyne, /ˈaɪ. ɵdɪn/ -o-dən, or (British English) /ˈaɪ. ɵdiːn/ -o-deen; from the Greek: ιώδης iodes, meaning violet or purple. Iodine and its compounds are primarily used in nutrition, the production of acetic acid and polymers. Iodine's relatively high atomic number, low toxicity, and ease of attachment to organic compounds have made it a part of many X-ray contrast materials in modern medicine. Like the other halogens, iodine occurs mainly as a diatomic molecule I2, not the atom...