Vanadium (V)

Around 85% of vanadium goes into steel, and a few tenths of a percent is enough to transform it: the Ford Model T's chassis used vanadium steel, which is a large part of why it was both light and durable. Vanadium ions change colour with oxidation state — lilac, green, blue, yellow for +2 through +5 — which makes it a standard lecture demonstration and is also what a redox flow battery is exploiting. Del Río found it in 1801, was talked out of the claim by a French chemist who insisted it was chromium, and had to watch it rediscovered and renamed thirty years later.

Properties

Atomic number

23

Symbol

V

Standard atomic weight

50.942 u

Category

Transition metal

Group

5

Period

4

Block

d-block

Electron configuration

[Ar] 4s² 3d³

Electrons per shell

2, 8, 11, 2

Melting point

2,183 K — 1909.8 °C — 3469.7 °F

Boiling point

3,680 K — 3406.8 °C — 6164.3 °F

Density

6 g/cm³

Electronegativity

1.63 (Pauling)

Oxidation states

+5, +4, +3, +2

Discovered

1801 by Andrés Manuel del Río; confirmed by Nils Gabriel Sefström in 1830

Electron configuration

Full

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d³

Noble gas shorthand

[Ar] 4s² 3d³

Shells

K: 2 · L: 8 · M: 11 · N: 2

What it is used for

• High-strength low-alloy steel for pipelines, springs and rebar
• Vanadium redox flow batteries for grid storage
• Vanadium pentoxide as the catalyst in sulfuric acid manufacture
• Titanium-aluminium-vanadium alloy in aerospace and implants

Neighbours in the table

Group 5

Elements in the same group share their outer electron count, which is why they behave similarly in reactions. Vanadium sits in group 5 with niobium, tantalum, dubnium.