Zinc Element Properties

Complete reference for zinc (Zn, element 30): atomic data, electron configuration, isotopes, physical constants, oxidation states, and a property unit converter.

30 Zn 65.38

Zinc

Post-transition Metal — Period 4, Group 12

Solid at STP Diamagnetic d-block

Atomic Identity

Atomic Number
30
Z
Symbol
Zn
German: Zink
Standard Atomic Wt.
65.38 u
IUPAC 2021
Period
4
Group
12
II B
Block
d-block
CAS Number
7440-66-6
Zn
Discovery
~1000 BCE (use)
India, early smelting
Name Origin
German: Zink
Possibly Persian Sing

Periodic Table Locator — Period 4 Neighborhood (d-block / p-block border)

29
Cu
Copper
Group 11
30
Zn
Zinc
Group 12
31
Ga
Gallium
Group 13
48
Cd
Cadmium
Period 5
80
Hg
Mercury
Period 6

Zinc (Z=30) sits at the end of the d-block in Period 4, between copper (Z=29) and gallium (Z=31) where the p-block begins. It is directly above cadmium (Z=48) and mercury (Z=80) in Group 12, forming the volatile-metal triad with its heavier congeners.

Electron Configuration

Full notation 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s²
Noble gas shorthand [Ar] 3d¹⁰ 4s²
Electrons per shell 2, 8, 18, 2
Valence electrons 12 (3d¹⁰ 4s²)
Unpaired electrons 0 (all subshells filled)
Magnetic ordering Diamagnetic
Note Standard filling order — no anomaly
Term symbol ¹S₀
Simplified Orbital Diagram
1s
2s
2p
3s
3p
3d
10e
4s
2e
30 electrons total — all subshells completely filled
No Anomaly

Both 3d and 4s fully filled — standard Aufbau order

Key Isotopes of Zinc

Isotope Symbol Protons Neutrons Mass (u) Abundance Stability
Zinc-64 ⁶⁴Zn 30 34 63.9291420 48.6% Stable
Zinc-65 ⁶⁵Zn 30 35 64.9292204 Radioactive Unstable
EC/β⁺; t½ = 243.93 d — radiotracer for biological Zn studies
Zinc-66 ⁶⁶Zn 30 36 65.9260334 27.9% Stable
Zinc-67 ⁶⁷Zn 30 37 66.9271273 4.1% Stable
Zinc-68 ⁶⁸Zn 30 38 67.9248442 18.8% Stable
Zinc-70 ⁷⁰Zn 30 40 69.9253193 0.6% Stable

Zinc has five stable isotopes (Zn-64, 66, 67, 68, 70), making it one of the elements with the most stable isotopes. Zn-64 is the most abundant at 48.6%. Zn-65 is an important radiotracer used to study zinc metabolism in plants, animals, and humans. The wide spread of stable isotopes is exploited in isotope dilution mass spectrometry for precise zinc quantification in environmental and biological samples.

Physical Properties

State at STP Solid (metal)
Color Bluish-white, lustrous
Luster Metallic; tarnishes dull gray in air
Density (25 °C) 7133 kg/m³ (7.133 g/cm³)
Melting Point 419.53 °C (692.68 K / 787.15 °F)
Boiling Point 907 °C (1180 K / 1665 °F)
Heat of Fusion 7.32 kJ/mol
Heat of Vaporization 115 kJ/mol
Specific Heat (25 °C) 25.470 J/(mol·K)
Thermal Conductivity 116 W/(m·K)
Electrical Resistivity 59.0 nΩ·m (20 °C)
Hardness (Mohs) 2.5
Crystal Structure HCP (hexagonal close-packed)
Lattice Parameter a = 266.49 pm, c = 494.68 pm

Chemical Properties

Electronegativity (Pauling) 1.65
Electron Affinity Not stable (≈ −58 kJ/mol)
1st Ionization Energy 906.4 kJ/mol
2nd Ionization Energy 1733.3 kJ/mol
3rd Ionization Energy 3833 kJ/mol
Covalent Radius 122 pm
Van der Waals Radius 139 pm
Ionic Radius (Zn²⁺) 74 pm (6-coord.)
Oxidation States 0, +2 (dominant); +1 (rare dimers)
Reactivity Moderate; reacts with dilute acids
Amphoteric Yes — reacts with strong bases
Magnetic Ordering Diamagnetic
Standard Potential (Zn²⁺/Zn) −0.7618 V
Activity More active than Fe; below Mn

Oxidation States of Zinc

State Ion / Form Example Compound Notes
0 Zn⁰ Zn metal, organozinc compounds Native zinc; Grignard-type organometallics
+1 Zn⁺ (Zn₂²⁺) Zn₂(AlCl₄)₂ (rare) Dimeric Zn(I) species in ionic liquids; highly unstable
+2 Zn²⁺ (zinc) ZnO, ZnS, ZnCl₂, ZnSO₄, Zn(OH)₂ Overwhelmingly dominant oxidation state in all common chemistry

Ground State Quantum Numbers

Principal (n) 3 (3d) / 4 (4s)
Azimuthal (l) — 3d 2 (d orbital)
Azimuthal (l) — 4s 0 (s orbital)
Magnetic (mℓ) −2 to +2 (d subshell)
Spin (mₛ) +½, −½ (both 4s electrons paired)
Term symbol ¹S₀
Spin multiplicity 1 (singlet — no unpaired electrons)
Degeneracy 1 (J = 0, only one state)

Notable Emission Lines

213.86 nm
UV (AAS primary)
307.59 nm
UV/Near-UV
330.26 nm
UV/Near-UV
334.50 nm
Near-UV
481.05 nm
Blue
636.23 nm
Red

In a flame test, zinc produces a blue-green flame. The 213.86 nm UV resonance line is the primary line used in atomic absorption spectroscopy (AAS) for zinc determination in water, soil, and food samples. Zinc spectral lines are widely used in analytical chemistry due to zinc's importance as an environmental and nutritional tracer.

Property Unit Converter

Convert common zinc property values between units. Enter a value and select the conversion.

Temperature
Celsius 419.53 °C
Kelvin 692.68 K
Fahrenheit 787.15 °F
Density
g/cm³ 7.1330 g/cm³
kg/m³ 7133.00 kg/m³
lb/ft³ 445.46 lb/ft³
Energy (per mol)
kJ/mol 906.40 kJ/mol
eV/atom 9.3942 eV
kcal/mol 216.70 kcal/mol

Common Zinc Compounds

Compound Formula Common Name Key Uses
Zinc oxide ZnO Zinc white / calamine Sunscreen, rubber vulcanization, pigment, LED phosphors, anti-dandruff shampoo
Zinc sulfide ZnS Sphalerite (ore mineral) Luminescent materials, photocatalysis, phosphor in CRT screens
Zinc sulfate ZnSO₄·7H₂O White vitriol Fertilizer additive, rayon manufacture, electrolyte in Zn electroplating
Zinc chloride ZnCl₂ Zinc butter Flux for soldering, textile treating, wood preservative, Lewis acid catalyst
Zinc carbonate ZnCO₃ Smithsonite (ore) Zinc ore source, mild antiseptic, calamine lotion ingredient
Zinc hydroxide Zn(OH)₂ Zinc hydroxide Precursor to ZnO, amphoteric — dissolves in acid and base
Zinc phosphide Zn₃P₂ Rodenticide (reacts with stomach acid to release PH₃)
Zinc acetate Zn(CH₃COO)₂ Zinc diacetate Cold and sore-throat lozenges, dietary supplement, wood preservation

Key Facts About Zinc

The Galvanizing Metal

Roughly half of all zinc produced worldwide is used for galvanizing: coating steel and iron with a thin zinc layer to prevent rust. Zinc's standard reduction potential (−0.76 V) is more negative than iron (−0.44 V), so zinc oxidizes preferentially, acting as a sacrificial anode. Even when the zinc coating is scratched, the surrounding zinc continues to protect the exposed iron electrochemically. Galvanized steel is ubiquitous in construction, automotive bodies, and outdoor infrastructure.

Essential Micronutrient

Zinc is the second most abundant transition metal in the human body after iron, with around 2–3 g present in an adult. It is a cofactor for over 300 enzymes, including carbonic anhydrase (CO₂ transport), alcohol dehydrogenase, RNA polymerase, and DNA polymerase. Zinc fingers — protein motifs that use a Zn²⁺ ion to fold DNA-binding domains — are among the most common structural motifs in the human genome. Zinc deficiency affects roughly 2 billion people worldwide and impairs immune function, wound healing, and growth.

Die-Casting Champion

Zinc alloys (mainly Zamak — zinc, aluminum, magnesium, copper) dominate die-casting because of their low melting point (380–420 °C for alloys), excellent fluidity in the mold, and superior surface finish. Zinc die castings appear in automotive door handles, toy cars, plumbing fixtures, and electronic connector housings. The low melting temperature reduces energy consumption and tool wear dramatically compared to aluminum or brass casting, making zinc die-casting economically favorable for complex small parts.

Batteries and Energy Storage

Zinc has a long history in batteries. The common alkaline battery (AA, AAA) uses a zinc anode and manganese dioxide cathode. Zinc-carbon batteries (Leclanché cells) were the first commercially successful dry cells. More recently, zinc-air batteries offer high energy density for hearing aids and emerging electric vehicle research. Zinc-ion rechargeable batteries are being studied as safer, cheaper alternatives to lithium-ion systems because zinc is abundant, non-flammable, and water-compatible.

Brass: The Alloy of Civilization

Brass, an alloy of copper (55–95%) and zinc (5–45%), has been produced since antiquity. Zinc's addition to copper lowers the melting point, increases strength, improves machinability, and gives the characteristic gold-like appearance. High-zinc brass (60%+ Zn) is used in musical instruments, cartridge cases, and plumbing fittings. Low-zinc brass (gilding metal, 95% Cu/5% Zn) is used for coins and jewelry. The Romans produced brass by cementation — heating copper with calamine (ZnCO₃) ore — without isolating zinc metal itself.

Sunscreen and Photocatalysis

Zinc oxide (ZnO) is a wide-bandgap semiconductor (3.37 eV) with excellent UV-blocking properties, making it a key ingredient in physical (mineral) sunscreens. Unlike organic UV filters, ZnO is photostable, non-irritating, and effective across both UVA and UVB wavelengths. Nanoparticle ZnO (20–50 nm) is transparent on skin and used in cosmetic-grade formulations. The same wide bandgap makes ZnO a photocatalyst for degrading organic pollutants under UV light, and a piezoelectric nanomaterial for nanogenerators and sensors.

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Summary

Complete reference for zinc (Zn, element 30): atomic data, electron configuration, isotopes, physical constants, oxidation states, and a property unit converter.

How it works

  1. Browse the atomic identity card for symbol, atomic number, and standard atomic weight.
  2. Check the electron configuration panel for orbital notation and the filled [Ar] 3d¹⁰ 4s² arrangement.
  3. Review the isotopes table for stable and notable radioactive isotopes with natural abundances.
  4. Consult the physical and chemical properties panels for melting point, density, ionization energies, and oxidation states.
  5. Use the interactive unit converter to convert zinc property values between common units.
  6. Explore the key facts section for industrial context and interesting chemistry of zinc.

Use cases

  • Look up zinc constants for chemistry homework, metallurgy, or materials science work.
  • Verify atomic data when writing lab reports or research papers.
  • Reference isotope data for radiochemistry or nuclear research.
  • Convert melting and boiling points between Celsius, Fahrenheit, and Kelvin.
  • Study d-block electron configurations using zinc as an example of a filled d-subshell.
  • Confirm the +2 oxidation state for writing ionic formulae or balancing redox equations.
  • Research zinc compounds for industrial chemistry, biology, or environmental science.
  • Quick-reference ionization energies for electrochemistry or spectroscopy calculations.

Frequently Asked Questions

Last updated: 2026-06-18 · Reviewed by Nham Vu