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Elements JKSSB
• Robert Boyle was the first scientist to use the term element in 1661.
• AntoineLavoisier (1743-94)wasthefirst toestablishanexperimentallyusefuldefinitionofanelement.
• Hedefinedanelementasabasicformofmatterthatcannotbebrokendownintosimplersubstances
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
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for the first time. For example, the name copper was taken from Cyprus.
• Somenamesweretakenfromspecificcolours.E.g.goldwastakenfromtheEnglishwordmeaningyellow.
• Now-a-days,IUPAC(InternationalUnionofPureAndAppliedChemistry)approvesnamesofelements.
• Manyof thesymbolsarethefirstoneor twolettersof theelement’snamein English.
• Thefirst letterofasymbolisalwayswrittenasanuppercaseandthesecondletterasalowercase.
