Selenium and Iodine - Comparison - Properties

This article contains comparison of key thermal and atomic properties of selenium and iodine, two comparable chemical elements from the periodic table. It also contains basic descriptions and applications of both elements. Selenium vs Iodine.

selenium and iodine - comparison

Compare selenium with another element

Compare iodine with another element

Selenium and Iodine – About Elements

Selenium

Selenium is a nonmetal with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth’s crust.

Iodine

Iodine is 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. Iodine is the least abundant of the stable halogens, being the sixty-first most abundant element. It is even less abundant than the so-called rare earths. It is the heaviest essential mineral nutrient.

Selenium in Periodic Table

Iodine in Periodic Table

Source: www.luciteria.com

Selenium and Iodine – Applications

Selenium

The chief commercial uses for selenium today are glassmaking and pigments. Selenium finds applications in the various industries, for example, solar cells and photoconductor applications, manganese electrolysis, DC power surge protection or X-ray crystallography.

Iodine

In addition to nutrition products, iodine and iodine derivatives are used in a wide range of medical, agricultural, and industrial applications. About half of all produced iodine goes into various organoiodine compounds, another 15% remains as the pure element, another 15% is used to form potassium iodide, and another 15% for other inorganic iodine compounds. The leading application is in the production of X-ray contrast media (22%). Iodine’s high atomic number and density make it ideally suited for this application, as its presence in the body can help to increase contrast between tissues, organs, and blood vessels with similar X-ray densities. It is used as an antiseptic for external wounds. Another application driving the demand for iodine is in polarizing film in liquidcrystal display (LCD) screens.

Selenium and Iodine – Comparison in Table

Element	Selenium	Iodine
Density	4.819 g/cm3	4.94 g/cm3
Ultimate Tensile Strength	300 MPa	N/A
Yield Strength	150 MPa	N/A
Young’s Modulus of Elasticity	10 GPa	N/A
Mohs Scale	2	N/A
Brinell Hardness	740 MPa	N/A
Vickers Hardness	N/A	N/A
Melting Point	221 °C	113.5 °C
Boiling Point	685 °C	184 °C
Thermal Conductivity	2.04 W/mK	0.449 W/mK
Thermal Expansion Coefficient	37 µm/mK	N/A
Specific Heat	0.32 J/g K	0.214 J/g K
Heat of Fusion	6.694 kJ/mol	7.824 kJ/mol
Heat of Vaporization	37.7 kJ/mol	20.752 kJ/mol