Platinum
Definition and meaning of Platinum in chemistry.
![Platinum element card: symbol Pt, atomic number 78, atomic mass 195.08, electron configuration [Xe] 4f¹⁴ 5d⁹ 6s¹, oxidation states +4 +2, Transition metal, group 10, period 6, solid at room temperature.](/assets/images/terms/platinum-chemical-element.webp)
Platinum is a dense, silvery-white transition metal with the atomic number 78. Its chemical symbol is Pt, and it acts as the namesake of the platinum group. People highly value this precious metal for its exceptional catalytic properties and strong corrosion resistance.
In more detail
Platinum sits in group 10 of the periodic table alongside palladium and nickel. It is classified as a noble metal because it demonstrates remarkable chemical stability. It remains unoxidized in normal air even when exposed to extremely high temperatures.
The metal strongly resists attack by most common acids found in chemistry laboratories. However, it will completely dissolve in hot aqua regia, a highly corrosive acid mixture. Platinum occurs naturally in the uncombined state as a native metal in the ground.
Miners often find it inside alluvial sands and primary magmatic metallic ore deposits. It frequently appears alongside other platinum-group metals, nickel, and copper in natural deposits. Platinum exhibits excellent ductility and malleability, making it very easy to shape physically.
Ductility means you can smoothly draw the solid metal into incredibly fine wires. Malleability means you can hammer it into extremely thin sheets without losing structural integrity. Chemically, the most common oxidation states of platinum are the +2 and +4 states.
These states allow it to form numerous highly stable chemical coordination complexes. Some of these specific complexes possess significant biological and medicinal activity against diseases. Platinum surfaces can adsorb hydrogen and oxygen gases rapidly at standard room temperature.
Adsorb means the gases stick tightly directly to the outer surface of the metal. This ability makes it an indispensable catalyst in various large-scale industrial chemical reactions. It is heavily used in petroleum refining and the commercial synthesis of nitric acid.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Pt |
| Atomic number | 78 |
| Atomic mass | 195.08 u |
| Category | Transition-Metal |
| State at room temperature | Solid |
| Melting point | 1768 degrees Celsius |
The largest commercial application of platinum is in the production of automotive catalytic converters. It facilitates the complete combustion of unburned hydrocarbons and toxic carbon monoxide gas. This vital chemical reaction quickly turns these harmful pollutants into harmless carbon dioxide and water vapor.
Frequently asked questions
Why is platinum considered a noble metal?
Platinum is a noble metal because it exhibits outstanding resistance to chemical attack and oxidation. It maintains its metallic shine and physical strength even in harsh, corrosive environments.
How is platinum used in medicine?
Certain platinum-based chemical complexes, notably cisplatin, are highly effective chemotherapeutic agents. They treat various cancers by binding directly to cellular DNA and triggering tumor cell death.
Related terms
Sources & references
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