How did scientists first determine what air is composed of?

Question

I searched on the web, and all I got are the usual components and what percent of air they make up. I'm more interested in how the components were discovered.

Answer 1

The first step was the realization that different items might be able to be separated out of the air. This was the innovation of a scientist named Jan van Helmont, and occurred around 1630. However, no real progress was made towards the discovery of the components for almost a century and a half. Then, in the 1770s, a scientist named Antoine-Laurent Lavoisier proposed that air had two main components: one that burned and one that didn't. Furthermore, he demonstrated that the combustible gas constituted approximately 20% of air and the non-combustible gas constituted approximately 80%. He called the combustible gas "oxygen" and the non-combustible gas "azote". Today, we know the non-combustible gas as nitrogen.

Of course, there's a lot more to the story than that, just like there's a lot more to the atmosphere than nitrogen and oxygen. That's just what is most important. If you want the full story, follow this link:

http://www.bookrags.com/sciences/sciencehistory/air-composition-wsd.html