4.2 quiz study guide Flashcards
what are the three types of subatomic particles?
protons, neutrons, electrons
how does the Rutherford model describe the structure of atoms?
○ atom is mostly empty space
○ nucleus is tiny and densely packed
○ a positively charged nucleus surrounded by electrons, which occupy most of the volume
what are the charges and relative masses of the three main subatomic particles?
proton: 1+ , mass = 1
neutron: 0, mass = 1
electron: charge 1- , mass = 1/1840
describe Thomson’s and Millikan’s contributions to atomic theory
○ thomson discovered electrons
○ millikan determined the quantity of charge and mass of electrons
compare Rutherford’s expected outcome of the gold-foil experiment with the actual outcome
he thought the alpha particles would have passed through the gold with only slight deflection
outcome: most alpha particles went straight through the gold foil. BUT a small fraction of them bounced off the foil at large angles
what experimental evidence led Rutherford to conclude that an atom is mostly empty space?
because majority of the alpha particles passed straight through the gold foil
how did Rutherford’s model of the atom differ from Thomson’s?
rutherford’s atomic model described the atom as having a positively charged dense nucleus that is tiny compared to the atom as a whole
in thomson’s plum-pudding model, electrons were stuck in a chunk of positive charge.
tell me about jj thomson
○ discovered electrons
○ plum pudding model
tell me about robert a millikan
○ oil-drop experiment (charge of each oil drop = 1.60x 10 to power of -19 coulomb)
○ determined the quantity of charge and mass of electrons
tell me about james chadwick
○ confirmed existence of neutrons
tell me about eugene goldstein
○ discovered protons
tell me about ernest rutherford
○ gold foil experiment
