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• Robert Boyle was the first scientist to use the term element in 1661.
• AntoineLavoisier (1743-94)wasthefirst toestablishanexperimentallyusefuldefinitionofanelement.
by chemical reactions.
• Element: A chemical element is a pure chemical substance consisting of asingle type of atom distinguished
by its atomic number, which is the number of protons in its atomic nucleus.
• Ifasubstancecannotbebrokendownfurtherbychemical reactions,bycooling,heating,orbyelectrolysis,
it is called ‘element’. Sulphur is an element. So is iron. Carbon, too, is an element.
• Elements are divided into metals, metalloids, and non-metals.
• Pure substances can be elements or compounds.
• In the beginning, the names of elements were derived from the name of the place where they were found
for the first time. For example, the name copper was taken from Cyprus.
• Manyof thesymbolsarethefirstoneor twolettersof theelement’snamein English.
• Thefirst letterofasymbolisalwayswrittenasanuppercaseandthesecondletterasalowercase.