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Vocabulary #12
8th Grade Science Vocabulary
Term | Definition |
---|---|
Valence electron | The outermost electron of an atom that participates in chemical bonding. |
Alkali metals | The metals in GROUP 1 of the periodic table; they are the most reactive metals; their atoms HAVE ONE VALENCE ELECTRON |
Alkaline-earth metals | The elements of GROUP 2 of the periodic table; they are very reactive metals but are less reactive than alkali metals; their atoms HAVE TWO VALENCE ELECTRONS |
Halogens | The elements in GROUP 17 of periodic table; they are very reactive nonmetals; their atoms HAVE SEVEN ELECTRONS |
Noble gases | The elements in GROUP 18 of the periodic table; they are unreactive nonmetals; their atoms HAVE EIGHT VALENCE ELECTRONS(except for helium, which has two electrons) |