Platinum (Pt)
Transition metal
Platinum is the standard-setter of precious metals — rare, untarnishable and catalytically gifted. It converts car exhaust, powers fuel cells, fights cancer in the drug cisplatin, and anchors jewellery worth more than gold historically.
Position on the periodic table
Atomic properties
| Atomic number | 78 |
|---|---|
| Atomic mass | 195.085 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 4f14 5d9 |
| Noble gas shorthand | [Xe] 4f14 5d9 6s1 |
| Electrons per shell | 2, 8, 18, 32, 17, 1 |
| Valence electrons (outer shell) | 1 |
| Common oxidation states | +2, +4 |
| Electronegativity (Pauling) | 2.28 |
| Covalent radius (approx.) | 136 pm |
| First ionization energy | 870 kJ/mol |
| Electron affinity | 205 kJ/mol |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 21.45 g/cm³ |
| Melting point | 1768.3 °C (2041.4 K) |
| Boiling point | 3824.8 °C (4098 K) |
| Appearance | silvery white |
| Radioactive | No |
| Origin | Occurs naturally |
Electron configuration of platinum
Platinum's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 4f14 5d9, usually shortened to [Xe] 4f14 5d9 6s1. Its electrons occupy 6 shells (2, 8, 18, 32, 17, 1), placing it in period 6 of the d-block. Explore it interactively in the electron configuration calculator.
Uses of platinum
- Catalytic converters
- Jewellery
- Chemotherapy drugs (cisplatin, carboplatin)
- Fuel cells and laboratory equipment
Biological role: None; platinum drugs act by binding DNA in cancer cells.
Occurrence: Very rare; mined mainly in South Africa's Bushveld complex.
Common compounds of platinum
PtCl2(NH3)2
Cisplatin
History and discovery
Discovered: 1735 — Antonio de Ulloa. Name origin: From Spanish platina, “little silver” — conquistadors first dismissed it as unripe silver.
Used by pre-Columbian South Americans; described for European science by Antonio de Ulloa in the 1740s.
Safety notes
Metallic platinum is inert; some platinum salts sensitise skin and airways.
Educational context only — always follow your school's laboratory rules and never handle chemicals without proper supervision. See our disclaimer.
Practice questions
Quick practice: Platinum
1. What is the chemical symbol of Platinum?
2. What is the atomic number of Platinum?
3. Which category does Platinum belong to?
4. What is the state of Platinum at room temperature?
5. Which period of the periodic table is Platinum in?
Platinum FAQs
What is the atomic number of platinum?
Platinum's atomic number is 78 — every platinum atom has 78 protons in its nucleus.
What is the symbol for platinum?
Pt. From Spanish platina, “little silver” — conquistadors first dismissed it as unripe silver.
Is platinum a metal, nonmetal, or metalloid?
Platinum is classified as a transition metal.
What state is platinum at room temperature?
At about 25 °C, platinum is a solid. It melts at 1768.3 °C.
What is platinum used for?
Key uses include: catalytic converters; jewellery; chemotherapy drugs (cisplatin, carboplatin).
Related elements
Keep working with this element
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