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Building blocks (everything is composed of elements


smallest amount of an element that retains the trait of the element (Fe)


smallest amount of a compound that retains the trait of the compound


a combination of atoms bound together with a specific trait (like water H2O


positively charged particle, 1 atomic mass unit (amu), found in nucleus


neutral particle, 1 amu, found in nucleus


negatively charged particle, practically no mass, found in the outsides


charged particle (either missing electron(s) or extra electron(s)


something that changes to tell you another thing is present


is the center of the atom (protons & neutrons tightly packed together)

electron orbitals

area where electrons are likely to be found

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