zinc

Zinc is a chemical element with the symbol Zn and atomic number 30. It is a bluish-white metal that is relatively brittle at room temperature but becomes malleable when heated. A thin oxide layer forms on exposed surfaces, providing corrosion resistance. In the periodic table it is classified as a transition metal.

Zinc occurs mainly in minerals such as sphalerite (zinc sulfide) and smithsonite (zinc carbonate). Commercial production starts with mining the ore, roasting it to convert zinc sulfide to zinc oxide, and then reducing and purifying the metal by electrolysis. Recycling of scrap metal is also an important source of zinc.

Zinc has a melting point of 419.5°C and a boiling point of 907°C, with a density of about 7.14 g/cm3. It readily forms alloys, notably brass (with copper) and various zinc die-casting alloys. It is used as a protective coating for steel through galvanization.

Zinc and its compounds have a wide range of applications. Zinc oxide is used in rubber, ceramics, glass, and cosmetics, and as a UV absorber in some sunscreens. Zinc is also used in batteries, including zinc-carbon and zinc-air types, and as a micronutrient in fertilizers and animal feeds.

Zinc is an essential trace element for humans and many organisms, required for numerous enzymes and for immune function, growth, and wound healing. Deficiency can cause growth impairment, immune dysfunction, and dermatitis, while excessive intake or inhalation of zinc oxide fumes can be toxic and may cause metal fume fever. Environmental and occupational exposure is managed to minimize risk.