Inert: definition in chemistry
Inert: Very unreactive. The noble gases are often called inert gases, although some of them can form compounds.
Noble gases are unreactive because their outer electron shells are full, so they have little tendency to gain, lose or share electrons. They are not completely inert, though: xenon forms compounds with fluorine and oxygen, and the first noble gas compound was made in 1962. Chemists use inert materials such as argon, nitrogen gas, platinum or glass when they want to keep something from reacting.
Examples
- Argon fills light bulbs so the hot filament does not burn up
- Helium is used in balloons because it is light and cannot burn
- Nitrogen gas is pumped into chip bags to keep chips from going stale
- Gold jewelry stays shiny for centuries because gold barely reacts
On the periodic table
The noble gases in group 18, on the far right of the table, are the most unreactive elements; among metals, gold and platinum are notably unreactive.