Iodine (I)

Iodine (I)
Symbol I
Atomic Number 53
Atomic Mass 126.9045 g.mol -1
Discovered by Bernard Courtois in 1811

Chemical Properties of Iodine

Group 17 Melting point 113.7°C, 236.7°F, 386.9 K  
Period 5 Boiling point 184.4°C, 363.9°F, 457.6 K
Block p Density (g cm−3) 4.933
Atomic number 53 Relative atomic mass 126.904
State at 20°C Solid Key isotopes 127I
Electron configuration [Kr] 4d10 5s5p5 CAS number 7553-56-2
ChemSpider ID 4514549 ChemSpider is a free chemical database

What is Iodine?

  • Iodine with the symbol ‘I’ is a dark grey or purple blackish nonmetallic element with atomic number 53 in the Periodic Table.
  • It is the least reactive and most electropositive halogen, even though it can form compounds with many elements.
  • It is mainly found on Earth as the water-soluble iodide in brine pools and oceans.
  • This element gives purple colour when heated.
  • It is not completely soluble in water and dissolves in a few solvents like carbon tetrachloride.
  • Iodine element is available naturally in air, soil, and water. The most important source of this element is oceans. There are even some minerals, which contain iodine in them.
  • Iodine is an essential component in humans for a proper functioning of the brain. The human body contains nearly 20 milligrams in the thyroid gland.

Uses or Applications of Iodine

  • The first commercial use of iodine is in photography. Louis Daguerre invented a technique for producing images on a piece of metal.
  • It is used in the pharmaceutical industry, printing industry and in the manufacturing of animal feed.
  • It is also used as a water purifier.
  • This element is used in almost all medicines that aid in cleaning wounds.

Environmental Effects of Iodine

  • Iodine present in the air combines with water particles and gets dissolved into water or soils. Plants absorb the dissolved Iodine from water and soil in the process of their growth. Humans or animals get iodine from the plant sources. Iodine present or dissolved in water will evaporate and get mixed up in the air.
  • Iodine may be radioactive but it is not harmful to life.

Frequently Asked Questions – FAQs


What foods contain iodine naturally?

The products with the highest iodine content include seaweed, milk, salmon, shrimp, and eggs. In fact, most table salt has been iodised, making it convenient to add iodine to your meals.


What does iodine do to the thyroid?

The thyroid gland has the role of taking iodine, present in many foods and transforming it into thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Thyroid cells are the only cells that can consume iodine inside the body. Such cells combine to make T3 and T4 the iodine and the amino acid tyrosine.


Does iodine detox the body?

Within our bodies, things like pesticides, ammonia, fluoride, bromine and so many other dangerous contaminants will work their way. The good news is that having enough iodine will help keep some of those toxins out of the body.


How long does iodine take to work?

It typically takes between one and three months to produce the effect of this treatment on the thyroid gland, with maximum benefit occurring three to six months after treatment. A single dose is usually effective in treating hyperthyroidism.


What are the benefits of taking iodine?

Fostering the well-being of thyroids. Iodine plays a crucial role in the well-being of thyroids. Reducing the exposure to other goitres. Administration of overactive thyroid gland. Treating thyroid cancer. Neurodevelopment during pregnancy. Improving cognitive function. Improving birth weight. May help treat fibrocystic breast disease.

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  1. Write the main uses of iodine as non-metals

    • Iodine has many commercial uses. Iodide salts are used in pharmaceuticals and disinfectants, printing inks and dyes, catalysts, animal feed supplements and photographic chemicals. Iodine is also used to make polarizing filters for LCD displays.