Zinc
Zinc is a bluish-white metal best known for protecting steel from rust and for its role as an essential trace nutrient. Compounds of zinc, especially the alloy brass, were used for thousands of years before the pure metal itself was reliably produced and recognized as a distinct element.
- Group · Period
- 12 · 4
- At room temp
- solid
- Melts at
- 692.68 K
- Density
- 7.134 g/cm³
- Discovered
- 1746
Uses
Zinc’s largest single use is galvanizing — coating iron and steel with a protective layer of zinc that prevents rust, extending the life of everything from guardrails and fencing to structural steel and car bodies. It’s also alloyed with copper to make brass, a durable and attractive metal used in fittings, musical instruments, and decorative hardware, and it’s a key ingredient in zinc-carbon and alkaline batteries.
Zinc is also biologically essential: the body needs a steady dietary supply for a properly functioning immune system, wound healing, and normal growth, and zinc deficiency is a recognized nutritional concern in parts of the world with limited access to zinc-rich foods.
History
Zinc-containing ores were used to make brass for thousands of years before anyone isolated pure zinc metal, largely because zinc tends to vaporize before typical smelting methods can fully extract it from ore. Distillation techniques capable of capturing and condensing pure zinc metal were developed in India and China centuries before similar methods reached Europe. German chemist Andreas Sigismund Marggraf is generally credited with establishing a reliable, well-documented method for producing pure zinc in Europe in 1746, helping firmly establish it as a distinct metallic element in Western chemistry.
Fun facts
- Zinc is an essential trace nutrient for humans, important for immune function and wound healing, and it's found in foods like meat, nuts, and legumes.
- Galvanizing — coating steel with a layer of zinc — protects the steel from rusting even if the coating gets scratched, because zinc corrodes preferentially.
- Alloyed with copper, zinc forms brass, a material that's been used for tools, instruments, and decorative objects for thousands of years.
Frequently asked questions
How does galvanizing actually protect steel from rust?
A layer of zinc coating acts as a physical barrier, but it also provides protection even where the coating is scratched: zinc is more reactive than iron, so it corrodes first and sacrifices itself, shielding the exposed steel underneath. This is why galvanized steel structures, from guardrails to rooftops, can resist rust for decades.
Why was pure zinc metal discovered so much later than brass, which contains zinc?
Zinc has an unusual property: it vaporizes at a temperature below what's needed to fully extract it from its ore using older smelting methods, so early metalworkers making brass were adding zinc ore directly to molten copper without ever isolating pure zinc metal. Producing pure zinc required distillation techniques capable of capturing the vaporized metal, which took much longer to develop in Europe.
Is zinc considered a heavy metal?
Zinc is sometimes grouped with heavy metals, but unlike toxic heavy metals such as lead or mercury, it's actually an essential nutrient the body needs in small amounts. Problems only arise from either a genuine deficiency or, at the other extreme, consuming far more zinc than the body needs, which is uncommon under normal circumstances.
Compounds
4 notable compounds containing Zn
- ZnCl2salt
Zinc chloride
A white, extremely water-absorbing solid that dissolves readily and acts as an effective flux, helping molten metal wet and bond to surfaces during joining processes.
Used for: Flux in soldering and galvanizing; wood preservative
- ZnOoxide
Zinc oxide
A fine white powder that is chemically stable and reflects UV light effectively, making it one of the most widely used zinc compounds in both consumer and industrial products.
Used for: Sunscreen and skin-protectant ointments; rubber manufacturing
- ZnSO4salt
Zinc sulfate
A colorless, highly soluble crystalline salt that supplies zinc ions for a range of agricultural and health applications, since zinc is an essential trace element for both plants and animals.
Used for: Dietary supplement and agricultural micronutrient fertilizer
- ZnSmineral
Zinc sulfide
A compound found naturally as the mineral sphalerite, the world's main zinc ore. Synthetic zinc sulfide is also well known for its ability to phosphoresce after exposure to light.
Used for: Primary zinc ore; historically used in glow-in-the-dark materials
Isotopes
32 known isotopes
Swipe to see all columns →
| Isotope | Natural abundance | Half-life | Decay mode | Mass excess | Binding energy / nucleon | Decay width |
|---|---|---|---|---|---|---|
| Zn-64 stable | 49.17% | Stable | — | -66,004.02 keV | 8,735.91 keV | — |
| Zn-66 stable | 27.73% | Stable | — | -68,899.23 keV | 8,759.63 keV | — |
| Zn-67 stable | 4.04% | Stable | — | -67,880.38 keV | 8,734.15 keV | — |
| Zn-68 stable | 18.45% | Stable | — | -70,007.15 keV | 8,755.68 keV | — |
| Zn-70 | 0.61% | 3.8E18 Y | Double beta-minus decay (100%), Double beta-minus decay | -69,564.75 keV | 8,729.81 keV | 3.80 × 10-42 eV |
Show all 32 isotopes
| Zn-54 | — | 1.59 ms | Two-proton emission (92%) | -5,702 keV | 7,742 keV | 2.87 × 10-13 eV |
| Zn-55 | — | 19.8 ms | Electron capture / beta-plus decay (100%), ECP (91%) | -14,270 keV | 7,904 keV | 2.30 × 10-14 eV |
| Zn-56 | — | 32.4 ms | Electron capture / beta-plus decay (100%), ECP (88%) | -25,390 keV | 8,106 keV | 1.41 × 10-14 eV |
| Zn-57 | — | 40 ms | Electron capture / beta-plus decay (100%), Beta-plus, proton emission (65%) | -32,550 keV | 8,231 keV | 1.14 × 10-14 eV |
| Zn-58 | — | 86.7 ms | Electron capture / beta-plus decay (100%), ECP (3%) | -42,298.87 keV | 8,395.95 keV | 5.26 × 10-15 eV |
| Zn-59 | — | 178.6 ms | Electron capture / beta-plus decay (100%), ECP (0.1%) | -47,215.68 keV | 8,473.78 keV | 2.55 × 10-15 eV |
| Zn-60 | — | 2.38 m | Electron capture / beta-plus decay (100%) | -54,174.47 keV | 8,583.05 keV | 3.19 × 10-18 eV |
| Zn-61 | — | 89.1 s | Electron capture / beta-plus decay (100%) | -56,348.91 keV | 8,610.31 keV | 5.12 × 10-18 eV |
| Zn-62 | — | 9.193 h | Electron capture / beta-plus decay (100%) | -61,168.09 keV | 8,679.35 keV | 1.38 × 10-20 eV |
| Zn-63 | — | 38.47 m | Electron capture / beta-plus decay (100%) | -62,213.43 keV | 8,686.29 keV | 1.98 × 10-19 eV |
| Zn-65 | — | 243.93 d | Electron capture / beta-plus decay (100%) | -65,912.02 keV | 8,724.27 keV | 2.16 × 10-23 eV |
| Zn-69 | — | 56.4 m | Beta-minus decay (100%) | -68,417.91 keV | 8,722.73 keV | 1.35 × 10-19 eV |
| Zn-71 | — | 2.42 m | Beta-minus decay (100%) | -67,328.79 keV | 8,689.04 keV | 3.14 × 10-18 eV |
| Zn-72 | — | 46.5 h | Beta-minus decay (100%) | -68,145.5 keV | 8,691.81 keV | 2.73 × 10-21 eV |
| Zn-73 | — | 24.5 s | Beta-minus decay (100%) | -65,593.41 keV | 8,648.35 keV | 1.86 × 10-17 eV |
| Zn-74 | — | 95.6 s | Beta-minus decay (100%) | -65,756.72 keV | 8,642.75 keV | 4.77 × 10-18 eV |
| Zn-75 | — | 10.2 s | Beta-minus decay (100%) | -62,558.92 keV | 8,592.5 keV | 4.47 × 10-17 eV |
| Zn-76 | — | 5.7 s | Beta-minus decay (100%) | -62,303.02 keV | 8,582.27 keV | 8.00 × 10-17 eV |
| Zn-77 | — | 2.08 s | Beta-minus decay (100%) | -58,789.2 keV | 8,530 keV | 2.19 × 10-16 eV |
| Zn-78 | — | 1.47 s | Beta-minus decay (100%) | -57,483.24 keV | 8,507.38 keV | 3.10 × 10-16 eV |
| Zn-79 | — | 0.746 s | Beta-minus decay (100%), Beta-minus, neutron emission (1.7%) | -53,432.3 keV | 8,450.58 keV | 6.12 × 10-16 eV |
| Zn-80 | — | 561.9 ms | Beta-minus decay (100%), Beta-minus, neutron emission (1%) | -51,648.62 keV | 8,423.55 keV | 8.12 × 10-16 eV |
| Zn-81 | — | 0.32 s | Beta-minus decay (100%), Beta-minus, neutron emission (7.5%) | -46,199.67 keV | 8,351.93 keV | 1.43 × 10-15 eV |
| Zn-82 | — | 166 ms | Beta-minus decay (100%), Beta-minus, neutron emission (69%) | -42,313.96 keV | 8,301.12 keV | 2.75 × 10-15 eV |
| Zn-83 | — | 117 ms | Beta-minus decay (100%), Beta-minus, neutron emission | -36,290 keV | 8,226 keV | 3.90 × 10-15 eV |
| Zn-84 | — | 53.6 ms | Beta-minus decay (100%), Beta-minus, neutron emission (73%), B-3N | -31,830 keV | 8,171 keV | 8.51 × 10-15 eV |
| Zn-85 | — | 637 ns | B-2N, Beta-minus, neutron emission, Beta-minus decay | -25,100 keV | 8,090 keV | 7.16 × 10-10 eV |