Daniel Rutherford, a Scottish physician and chemist, discovered nitrogen in 1772 while conducting experiments to understand the nature of air. He was intrigued by the components of air that did not support combustion or respiration. To isolate the gas, he followed a series of methodical steps.
Rutherford used a process of removing oxygen from air, which involved letting a flame consume oxygen in a closed jar. As the flame extinguished, there was a decrease in the volume of air, indicating that a component had been used up. After the flame went out, Rutherford observed that the remaining gas did not support combustion or sustain life, leading him to realize that this component was different from oxygen and could be a distinct element.
He initially referred to the gas as ‘phlogisticated air’, a term derived from the popular phlogiston theory of the time. However, he later came to recognize it as a unique gas and is often credited with the discovery of what we now know as nitrogen. Through his experiments, Rutherford effectively contributed to the understanding of atmospheric gases and laid groundwork for future studies in chemistry and gas properties.