Chemical

Products

Iodine

Cas Number

7553-56-2

Other Names

-

The formula

I

Introduction

Iodine is a chemical element with symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a lustrous, purple-black metallic solid at standard conditions that sublimes readily to form a violet gas.

Physical and Chemical Properties
Melting point 386.85 K ​(113.7 °C, ​236.66 °F)
Boiling point 457.4 K ​(184.3 °C, ​363.7 °F)
Density (near r.t.) 4.933 g/cm3
Triple point 386.65 K, ​12.1 kPa
Critical point 819 K, 11.7 MPa
Solubility in water 633 g/L
Heat of fusion (I2) 15.52 kJ/mol
Heat of vaporisation (I2) 41.57 kJ/mol
Molar heat capacity (I2) 54.44 J/(mol·K)
Thermal conductivity 0.449 W/(m·K)
Electrical resistivity 1.3×107 Ω·m (at 0 °C)
Magnetic ordering diamagnetic[2]
Magnetic susceptibility −88.7·10−6 cm3/mol (298 K)[3]
Bulk modulus 7.7 GPa
Thermal conductivity 0.449 W/(m·K)
Electrical resistivity 1.3×107 Ω·m (at 0 °C)
Magnetic ordering diamagnetic[2]
Magnetic susceptibility −88.7·10−6 cm3/mol (298 K)[3]
Bulk modulus 7.7 GPa
Applications

1. Biocides Iodine-based biocides are used in industrial applications such as paints, adhesives, wood treatment and metalworking fluids.

2. LCD/LED polarizing films Liquid crystal displays utilize two sheets of polarizing material with a liquid crystal solution between them. Iodine is a key component in these polarizing films.

3. Human Nutrition Iodine is important in human nutrition, as the body needs to have a certain quantity of iodine to avoid conditions such as goiters, thyroid malfunctioning and potential mental retardation and abnormal growth in developing fetuses. Salt is iodized practically all over the word, in attempt to prevent these conditions.

4. X-ray contrast media Iodine is extensively used in the pharmaceutical industry, as a raw material for x-ray contrast media and antiseptics, as well as a catalyst or reagent in the synthesis of several active pharmaceutical ingredients such as antibiotics, corticosteroids and cardiovascular drugs.