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Atom words
atom defintions
word | definition |
---|---|
element | a puresubstance that can not be broken chemicaly or phyisacl means |
compound | a pure substance coposed of two or more elements that are chemically combined |
mixture | a combination of two or more substaces not combined chemically |
atom | the smallest particle into which an element can be divided and still retain all of the properteis of that element |
proton | the positively charged particles of the nucleus |
electron | the negativly charged particles found in the nucleus |
neutron | the particles of the nucleus that have no charge |
periodic law | a law that states that the chemical and physical properties of elements are periodic functions |
atomic numbers | the number of protrons in the nucleus |
atomic mass | the weighted average the masses of all naturaly occuring isotopes of an element |
isotope | atoms that have the same nuber of protrons but difrent number of nutrons |
valence electrons | the electrons in the outermost enrgy level of the atom |
john dalton | atom theory |
JJ Thomson | small particles in atom |
ernest rutherford | positive charged nucleus, atom mostly empty space electrons travel around nucleus |
niels bohr | electrons travel in clouds |
democritus | 1st to come up with idea of atom |
dmiti mendelev | father of the periodic table, arrange elements by atomic mass |
henry moseley | reaganged periodic table ny atmoic number |