What is the composition of air

Air is composed of a mixture of many gases that include oxygen, nitrogen, argon, carbon dioxide, neon, helium, krypton, xenon and nitrogen. They all differ in there abundance, nitrogen is the most abundant gas at 78.09%, oxygen at 20.95%, argon at 0.93%, Carbon dioxide at 0.038% and the remaining gases neon, helium, krypton, xenon and hydrogen occupy less than 0.002% each.