According to early chemists, which substances were classified as elements?

Asked Oct 08, 2013
In 1661 Boyle defined an element as a substance that cannot be broken down into a simpler substance by a chemical reaction. This simple definition actually served for nearly 301 years (until the development of the notion of subatomic particles), and even today is taught in introductory chemistry classes.
Answered Dec 14, 2013

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