Zinc or Zinc


Zinc or also known as zinc, is a chemical element of the periodic table, with atomic number 30 and symbol Zn, and is located in one of the groups of transition metals. The etymology of zinc apparently comes from the German, Zincken or Zacken (points, teeth), to indicate the aspect with jagged edges of the calamine mineral, later it was used for the metal obtained from it.

This metal is not found freely in nature, combined it is found abundantly, mainly in the mineral sphalerite or sphalerite (ZnS), as well as the minerals zincite (ZnO), hemimorphite, smitsionite and franklinite.

Zinc is extracted from natural sulfides (blendes) by calcination and reduction, another method is to treat the ground ores, with sulfuric acid, forming zinc sulfate, which is then subjected to electrolysis.

Among its properties are that it is bluish white; it is rough and brittle (it softens between 100-150 ºC) to the point where it can be pulverized, it has a melting point of 419 ºC and a boiling point of 907 ºC.

It has, of all the metals, the highest coefficient of thermal expansion. And of the heavy metals, it is the most electropositive; hence it displaces the other metals from their solutions. This is the reason why zinc is used as electro-negative in dry cell batteries and others.

In air, zinc oxidizes, but only slightly, perhaps due to the formation of a self-protective layer of oxide and carbonate. Because of its ability to resist corrosion well, and because it provides cathodic protection to iron, it is often used to coat iron to prevent rust from forming. The iron thus protected is called galvanized iron.

Zinc is a very important metal as it has many industrial applications; one of them are alloys, such as brasses (copper and zinc alloys), and Al and Mg alloys. Zinc oxide is used as a pigment in paint, it is also used as a filler in rubber tires and as an antiseptic ointment in medicine.

Zinc salts kill putrefactive bacteria and therefore are used to impregnate wood and poles, preserving them from putrefaction, highlighting that these salts are poisonous to animals and man.