History of the Atom Flashcards
what did jj thompson discover
electrons and the plum pudding model
who did the scattering experiment
ernest rutherford
what particles were fired at the gold foil-se
alpha
where did the particles go-se
through the foil
what did rutherford think atoms where filled with
empty space and positive nucleas
what did bohr discover
electrons are arranged in energy levels called shells
what did Dalton discover
that atoms were solid spheres
what did JJ Thompson conclude
that atoms weren’t solid spheres and that there had to be a charge and mass, and even smaller negatively charged atoms
what does the plum pudding model show
ball of positive charge with electrons stuck in it
when did Mendeleev create the periodic table?
1869
difference between the plum pudding model and the nuclear model
ppm vs. nm
atom is mostly positive charged ball - atom is mainly negative space
negative electrons randomly inside the positive ball - negative electrons orbit the nuclear at a distance
the mass is evenly distributed - most of the mass is concentrated in the positive nuclei
which particle was discovered to change the model of the atom
the electron
what did Bohr change about the nuclear model?
the electrons arranged in energy shells
why did Mendeleev change the order of some pairs of elements?
Mendeleev found that some elements did not fit the pattern in his table
