Gas that is part of the soil.

So, it is oxygen that is part of the soil. This colorless gas can contain up to twenty percent. I think everyone knows that this gas is also part of the air. But the first mentions of this gas were back in the eighth century. They were found in the manuscripts of a Chinese alchemist. But oxygen was officially discovered only in the second half of the eighteenth century, namely in 1744. All plants that exist on our planet annually form about three trillion tons of this colorless gas.