Vanadium
Atomic Data
| Atomic Number | 23 |
| Symbol | V |
| Atomic Weight | 50.942 u |
| Density (STP) | 6.0 g/cm³ |
| Melting Point | 1909.85 °C (2183 K) |
| Boiling Point | 3406.85 °C (3680 K) |
| Electronegativity | 1.63 (Pauling) |
| Electron Config. | 1s2 2s2 2p6 3s2 3p6 3d3 4s2 |
| Oxidation States | +2, +3, +4, +5 |
| Phase at STP | Solid |
| Category | Transition Metal |
| Period / Group | 4 / 5 |
| CAS Number | 7440-62-2 |
Electron Configuration
[Ar] 3d3 4s2
| Shell | n | Subshell | Electrons | Cumulative |
|---|---|---|---|---|
| K | 1 | 1s | 2 | 2 |
| L | 2 | 2s | 2 | 4 |
| L | 2 | 2p | 6 | 10 |
| M | 3 | 3s | 2 | 12 |
| M | 3 | 3p | 6 | 18 |
| M | 3 | 3d | 3 | 21 |
| N | 4 | 4s | 2 | 23 |
| Total | 23 | 23 | ||
Isotopes of Vanadium
Vanadium has two naturally occurring stable isotopes. The most abundant is ⁵¹V, comprising 99.75% of all naturally occurring Vanadium.
| Isotope | Symbol | Protons | Neutrons | Abundance | Stability |
|---|---|---|---|---|---|
| Vanadium-50 | ⁵⁰V | 23 | 27 | 0.25 | Stable |
| Vanadium-51 | ⁵¹V | 23 | 28 | 99.75 | Stable |
Abundance & Occurrence
Vanadium is present in Earth's crust at approximately 120 ppm by mass and at approximately 1 ppm by mass throughout the universe.
Earth's Crust (ppm by mass)
Universe (ppm by mass)
Discovery & History
Read more about the discovery of the periodic table of elements →
Safety & Handling
- Dust and fume toxicity: Vanadium pentoxide (V2O5) dust and fumes are acutely toxic by inhalation, causing chemical pneumonitis, bronchospasm, and potentially pulmonary oedema; it is classified as a possible human carcinogen (IARC Group 2B).
- Skin and mucous membrane irritation: Vanadium compounds cause irritation of the skin, eyes, and respiratory tract; green tongue is a characteristic but benign sign of vanadium exposure.
- Systemic toxicity: Systemic absorption of vanadium compounds interferes with cellular enzyme systems; chronic exposure can affect the kidneys, liver, and nervous system.
- Metal powder fire hazard: Vanadium metal powder is combustible; metal fires require Class D extinguishing agents.
Vanadium in the Real World
Real-World Uses
- High-strength steel alloys: Vanadium microalloying (0.1–0.3%) significantly increases the yield strength and toughness of structural steel used in pipelines, automotive chassis, bridges, rebar, and tool steels including high-speed steel (HSS).
- Vanadium redox flow batteries: Vanadium electrolyte-based redox flow batteries store electrical energy in dissolved vanadium ion solutions and are scalable grid-storage systems suitable for balancing renewable energy generation.
- Catalysis: Vanadium pentoxide (V₂O₅) is the catalyst in the contact process for manufacturing sulfuric acid, one of the world's most produced industrial chemicals, oxidising SO₂ to SO₃.
- Titanium alloys: Vanadium is a key alloying element in Ti-6Al-4V, the most widely used titanium alloy in aerospace and medical applications, where it stabilises the beta phase and improves workability.
- Pigments and ceramics: Vanadium compounds produce the vivid yellow colour of bismuth vanadate pigment used in high-performance paints and plastics, and add blue and green tints in glass and ceramic glazes.
Downloadable Resources
Free periodic table reference sheets for classrooms, study sessions, and laboratory use.
Frequently Asked Questions
What is vanadium used for?
Vanadium is used mainly as an alloying element in steel, where small additions produce high-strength low-alloy (HSLA) steels used in construction, pipelines, and automotive parts. Vanadium pentoxide is an industrial catalyst in the production of sulfuric acid, and vanadium redox flow batteries are a growing technology for large-scale energy storage.
Is vanadium toxic?
Vanadium compounds, particularly vanadium pentoxide dust, are toxic and can irritate the respiratory system and skin. However, trace amounts of vanadium appear to be beneficial in human metabolism, and it is found naturally in many foods. Occupational exposure during vanadium processing requires careful controls.
How was vanadium discovered?
Vanadium was first discovered in 1801 by Andrés Manuel del Río in Mexico, who initially called it erythronium but was later convinced he had simply found chromium. It was rediscovered in 1830 by Swedish chemist Nils Gabriel Sefström in iron ore from a mine in Taberg, and named after the Norse goddess Vanadis (Freya) for its beautiful multicoloured compounds.
What are vanadium redox batteries?
Vanadium redox flow batteries store energy in liquid vanadium electrolytes held in external tanks. Because both the positive and negative electrolytes use vanadium ions, there is no cross-contamination between the two sides, giving these batteries a very long cycle life. They are well-suited for grid-scale energy storage alongside renewable power sources.