- Fluorescent tube contents make strange groan - Gas, Ar - Inert gas - Inert gas, Ar - Noble gas - A substance regarded as an element, contained in the
atmosphere and remarkable for its chemical inertness.
- Balloon gas - Gaseous element, symbol He - Inert gas - Light gas - Noble gas - A gaseous element found in the atmospheres of the sun and
earth and in some rare minerals.