Zinc is a silver-gray metal with element symbol Zn and atomic number 30. The element is essential for human life and widely used in commercial applications. These zinc facts include basic facts, chemical and physical properties, and interesting trivia about the element.
Basic Zinc Facts
Atomic Number: 30
Element Symbol: Zn
Atomic Mass: 65.38(2)
Group: group 12
Period: period 4
Element Family: post-transition or transition metal
Electron Configuration: [Ar] 3d10 4s2
Discovery: Zinc was discovered by Indian metallurgists sometime before 1000 BCE. It was recognized as a new metal by Indian alchemist Rasaratna Samuccaya in the year 800. German chemist Andreas Sigismund Marggraf first isolated the pure element in 1746.
Name Origin: The name “zinc” was documented by Paracelsus, who referred to the metal as “zincum” or “zinken” in his book Liber Mineralium II in the 16th century. Presumably, it derives from the German word zinke, which means “tooth-like” or “jagged.” This refers to the needle-like appearance of zinc crystals. Zinc had numerous alchemy symbols.
Isotopes: Natural zinc consists of a mixture of five isotopes. The most abundant isotope is 64Zn. While technically a radioisotope, its half-life is so long (4.3×1018 years) that it is considered to be stable. Several dozen radioisotopes of zinc have been synthesized.
Uses: Zinc is the 4th most commonly used industrial metal, after iron, aluminum, and copper. Approximately half of the 12 million tons of zinc produced annually goes to galvanization. About 17% of production goes to manufacturing brass and bronze. Zinc compounds are also important. Zinc oxide occurs in paints and sunscreen.
Biological Activity: Zinc is essential nutrient. The human body uses it for enzymatic reactions, egg fertilization, white blood cell formation, and cell division. Zinc deficiency is one cause of age-related vision deterioration. However, too much zinc causes problems. Excess zinc suppresses iron absorption and can lead to permanent loss of the senses of smell and taste. The FDA issued warnings about zinc swabs and sprays to raise awareness of the risks.
Sources: About 95% of mined zinc derives from zinc sulfide ore. Zinc is highly recyclable. Around 30% of zinc in use today is recycled metal.
Density (room temperature): 7.14 g/cm3
Melting Point: 692.68 K (419.53 °C, 787.15 °F)
Boiling Point: 1180 K (907 °C, 1665 °F)
State at 20 ºC: Solid
Heat of Fusion: 7.32 kJ/mol
Heat of Vaporization: 115 kJ/mol
Molar Heat Capacity: 25.470 J/(mol·K)
Magnetic Ordering: diamagnetic
Crystal Structure: hexagonal close-packed (hcp)
Mohs Hardness: 2.5
Electronegativity: 1.65 (Pauling)
Atomic Radius: 134 pm (empirical)
Covalent Radius: 122±4 pm
Van der Waals Radius: 139 pm
1st Ionization Energy: 906.4 kJ/mol
2nd Ionization Energy: 1733.3 kJ/mol
3rd Ionization Energy: 3833 kJ/mol
Oxidation States: The most common oxidation state is +2. Other oxidation states include -2, 0, and +1.
10 Zinc Facts
- Zinc is the second most abundant metal in the human body, after iron.
- Ingesting zinc coins (such as U.S. pennies) can cause zinc intoxication and may be fatal. Zinc reacts with hydrochloric acid in the stomach, corroding the gastrointestinal tract.
- Zinc salts burn with a characteristic blue-green flame.
- Although galvanization protects other metals from corrosion, zinc actually does oxidize in air. A layer of zinc carbonate forms, which protects underlying metal from further attack.
- Zinc is the 24th most abundant element in the Earth’s crust. It is the 30th most abundant element in seawater.
- The ancient Greeks and Romans knew of zinc and used it, but not as often as iron or copper. This is probably because zinc boils away from most ores before it can be extracted. While ancient people usually used zinc as an alloy, a sheet of zinc from Athens dates to 300 B.C.
- Although Margraaf gets credit for isolating the element, English metallurgist William Champion patented a process to isolate zinc years earlier.
- Rinnmann’s test for zinc is a chemical indicator of the element. The test uses cobalticyanide paper, which turns green in the presence of the element.
- The world’s first pills consisted of zinc carbonates. The pills, discovered on a Roman ship that wrecked in 140 BC, were used to soothe sore eyes.
- Alchemists burned zinc in air to produce zinc oxide. Because of its appearance, zinc oxide was called lana philosophica (“philosopher’s wool”) or nix album (“white snow”).
- Emsley, John (2001). “Zinc”. Nature’s Building Blocks: An A-Z Guide to the Elements. Oxford, England, UK: Oxford University Press. pp. 499–505. ISBN 0-19-850340-7.
- Greenwood, N. N.; Earnshaw, A. (1997). Chemistry of the Elements (2nd ed.). Oxford: Butterworth-Heinemann. ISBN 0-7506-3365-4.
- Lehto, R. S. (1968). “Zinc”. In Clifford A. Hampel. The Encyclopedia of the Chemical Elements. New York: Reinhold Book Corporation. pp. 822–830. ISBN 0-442-15598-0.
- Lide, David R., ed. (2006) Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press, Taylor & Francis Group. ISBN 0-8493-0487-3.