Nickel (Ni)
Transition metal
Nickel is a tough, corrosion-resistant metal found in stainless steel, rechargeable batteries and coins. Meteorites carry a telltale nickel-iron signature, and the Earth's core is thought to contain vast amounts.
Position on the periodic table
Atomic properties
| Atomic number | 28 |
|---|---|
| Atomic mass | 58.6934 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d8 |
| Noble gas shorthand | [Ar] 3d8 4s2 |
| Electrons per shell | 2, 8, 16, 2 |
| Valence electrons (outer shell) | 2 |
| Common oxidation states | +2 |
| Electronegativity (Pauling) | 1.91 |
| Covalent radius (approx.) | 124 pm |
| First ionization energy | 737.1 kJ/mol |
| Electron affinity | 111.7 kJ/mol |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 8.908 g/cm³ |
| Melting point | 1454.8 °C (1728 K) |
| Boiling point | 2729.8 °C (3003 K) |
| Appearance | lustrous, metallic, and silver with a gold tinge |
| Radioactive | No |
| Origin | Occurs naturally |
Electron configuration of nickel
Nickel's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d8, usually shortened to [Ar] 3d8 4s2. Its electrons occupy 4 shells (2, 8, 16, 2), placing it in period 4 of the d-block. Explore it interactively in the electron configuration calculator.
Uses of nickel
- Stainless steel (its biggest use)
- Rechargeable batteries (NiMH, and nickel-rich Li-ion cathodes)
- Coins and corrosion-resistant plating
- Catalyst for hydrogenating vegetable oils
Biological role: Needed in trace amounts by some plants and microbes; no confirmed human requirement.
Occurrence: Mined from sulfide and laterite ores; abundant in meteorites.
Common compounds of nickel
NiO
Nickel(II) oxide
NiSO4
Nickel(II) sulfate
History and discovery
Discovered: 1751 — Axel Fredrik Cronstedt. Name origin: From German Kupfernickel (“devil's copper”) — ore that looked like copper but yielded none.
Axel Fredrik Cronstedt isolated nickel in 1751 from the ore that had frustrated copper miners.
Safety notes
Nickel is the most common cause of contact-allergy skin rashes, which is why jewellery is often labelled nickel-free.
Educational context only — always follow your school's laboratory rules and never handle chemicals without proper supervision. See our disclaimer.
Practice questions
Quick practice: Nickel
1. What is the chemical symbol of Nickel?
2. What is the atomic number of Nickel?
3. Which category does Nickel belong to?
4. What is the state of Nickel at room temperature?
5. Which period of the periodic table is Nickel in?
Nickel FAQs
What is the atomic number of nickel?
Nickel's atomic number is 28 — every nickel atom has 28 protons in its nucleus.
What is the symbol for nickel?
Ni. From German Kupfernickel (“devil's copper”) — ore that looked like copper but yielded none.
Is nickel a metal, nonmetal, or metalloid?
Nickel is classified as a transition metal.
What state is nickel at room temperature?
At about 25 °C, nickel is a solid. It melts at 1454.8 °C.
What is nickel used for?
Key uses include: stainless steel (its biggest use); rechargeable batteries (nimh, and nickel-rich li-ion cathodes); coins and corrosion-resistant plating.
Related elements
Keep working with this element
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