who proposed the modern idea of an element and when
History of the periodic table Lavoisier's Traité Élémentaire de Chimie (Elementary Treatise of Chemistry), which was written in 1789 and first translated into English by the writer Robert Kerr, is considered to be the first modern textbook about chemistry. Lavoisier defined an element as a substance that cannot be broken down into a simpler substance by a chemical reaction.[6] This simple definition served for a century and lasted until the discovery of subatomic particles. Lavoisier's book contained a list of "simple substances" that Lavoisier believed could not be broken down further, which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulfur, which formed the basis for the modern list of elements. Lavoisier's list also included 'light' and 'caloric', which at the time were believed to be material substances. He classified these substances into metals and non metals. While many leading chemists refused to believe Lavoisier's new revelations, the Elementary Treatise was written well enough to convince the younger generation. However, Lavoisier's descriptions of his elements lack completeness, as he only classified them as metals and non-metals.