zinku

Zinku, known in English as zinc, is a chemical element with the symbol Zn and atomic number 30. It is a bluish-white, relatively brittle metal at room temperature that becomes malleable when heated. Zinc has a relatively low melting point of 419.5°C and a boiling point of 907°C. It resists corrosion by forming a protective oxide layer, a property exploited in galvanization to protect iron and steel from rust.

Zinku occurs mainly in the mineral sphalerite (zinc sulfide) and is geographically widespread. Other important ores include smithsonite (zinc carbonate) and calamine. The metal is extracted by mining, roasting of the ore, and reduction; purification is typically achieved by electrolytic refining to yield high-purity zinc. Globally, zinku is the fourth most widely used metal.

Applications of zinku include the largest use in galvanizing steel to prevent corrosion. It is also used to produce brass (an alloy of copper and zinc), in die-casting alloys, and to manufacture zinc oxide, which is employed in rubber manufacturing, coatings, pigments, ceramics, and some sunscreen products. Zinc is also a component in batteries, notably zinc-carbon and alkaline cells.

Biological role: Zinc is an essential trace element for humans and many organisms, participating in enzyme function, protein synthesis, immune response, and wound healing. Excess intake or exposure to zinc fumes can cause health problems, and very high zinc levels can interfere with copper absorption.

History: Zinc has been known since antiquity in brass and related alloys. It was isolated as a free metal in the 18th century, with metallic zinc first produced in 1746 by Andreas Marggraf.

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