Argon is the third most common noble gas in the atmosphere. Argon gas is therefore a natural component of the atmosphere as part of the air we breathe. It is an inert gas that is denser than nitrogen and twice as dense as neon. Argon is heavier than air. At room temperature, argon is a colorless and odorless gas.
Its most important property is its inertness—argon does not burn and reacts only slightly, if at all, with potential reaction partners such as water or air. However, if a voltage is applied to pure argon in gas discharge tubes, a current flows. The argon gas produces red-violet light during glow discharge.
