Nitrogen
A physician named Daniel Rutherford discovered nitrogen in Scotland in 1772. It was studied by other chemists around the same time but they called i air without oxygen or it was also known as “burnt or dephlogisticated air.” French chemist Antoine Laurent Lavoisier recognized nitrogen as an elemental gas around 1776. Nitrogen is a colourless, odourless, tasteless, and non-toxic gas. It makes up about 78% of the air on Earth, by volume, which makes it the most plentiful element in the atmosphere. Earth’s atmosphere is made up of more than 4000 trillion tons of nitrogen. Nitrogen can be obtained from the atmosphere by passing air over heated copper or iron, which removes oxygen and leaves nitrogen and mixed gases. Pure nitrogen is obtained from liquefied air through a process known as fractional distillation because nitrogen has a lower boiling point than oxygen and can distil off first.
