Tag: composition of air

Oxygen exists as $O _2$. Hence each molecule of oxygen gas contains 2 atoms.

The air in our atmosphere is composed of molecules of different gases. The most common gases are nitrogen (78%), oxygen (about 21%), and argon (almost 1%).

Nitrogen and oxygen gases are the major components of the atmosphere. Around 80% of the atmosphere is nitrogen and 20% is oxygen, by volume. 

Xenon is a noble gas present in the Earth's atmosphere in extremely low concentrations (about 0.087 ppm). While neon, helium, and argon are also inert, xenon is significantly rarer than the others listed.

Air consists of active and inactive components. This was proposed by Mayow in the year 1674.

Noble gases have the largest ionization potential among the elements of each period, which reflects the stability of their electron configuration and is related to their relative lack of chemical reactivity.

The noble gases have weak interatomic force, and consequently have very low melting and boiling points. They are all monatomic gases under standard conditions, including the elements with larger atomic masses than many normally solid elements.

The noble gases make a group of chemical elements with similar properties. For the first six periods of the periodic table, the noble gases are exactly the members of group 18 of the periodic table.

The abundances of the noble gases decrease as their atomic numbers increase. Helium is the most plentiful element in the universe except hydrogen. All the noble gases are present in Earths atmosphere and, except for helium and radon, their major commercial source is the air, from which they are obtained by liquefaction and fractional distillation.

An inert gas is a gas that is generally non-reactive with other substances. The term inert means non-reactive. We refer to gases as being chemically inert if their atoms don't combine with other atoms in chemical reactions.