colorless gas
Clear airborne substance
A colorless gas is one that cannot be seen—transparent to the eye, like air itself.
The phrase appears constantly in chemistry and safety contexts to describe substances like oxygen, nitrogen, hydrogen, and carbon monoxide: Radon is a colorless, odorless gas that can accumulate in basements.
The descriptor matters because visibility affects detection of leaks or contamination.
- odorlessHaving no smell
- argonUnreactive element eighteen
- methaneSimplest alkane fuel
- greenhouse gasHeat-trapping atmospheric compound
- hydrogenSimplest atomic element
lighter than air · asphyxiant · inert · helium · tasteless · refrigerant · nitrogen · carbon dioxide · neon · toxic gas · gas mask · compressible · oxygen · industrial use · boiling point · fuel source · propane tank · pollutant