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atom stack
Term | Definition |
---|---|
Democritus | thought of atoms (atomos... etc) |
aristotle | said matter was continuous |
1790 Joseph lois proust | law of definite masses |
law of definite masses | masses of chemical substances combine in definite repeatable ratios when forming compounds |
John Dalton | heat envelope |
jj thompson | plum pudding |
rutherford | nuclear model |
chadwick | discovered nuetrons |
Niels Bohr | planetary model (electron energy levels) |
quantum models | e clouds orbit |
orbitals | quantum model |
orbits | planetary model |
nuetrons | biggest |
different numbers of nuetrons | isotopes |
mass number | protons+nuetrons |
octet rule | atom is happiest with 8 valence electrons |
atomic mass | mass of atom measured im AMU's |
nuclear radiation | emission of rays or particles from unstable nuclei |
alpha particle | 2 protons and 2 nuetrons (positively charged) |
beta particle | free electron (nuetron also changes to proton) |
gamma rays | em waves |
half life | how long it takes for a half of a sample to decay |