9/6 class notes Flashcards
Thomson’s cathode ray experiment procedue
apply high voltage to device (be able to draw)
Thomson’s cathode ray experiment observations
beam of particles moving from cathode (negative electrode) to anthode (positive)
Thomson’s cathode ray experiment conclusion
atoms of the gas must contain negative charged particles (electrons)
Thomson’s cathode ray experiment 1st follow up experiment procedure, conclusion
procedure: apply magnetic field (electric field) to deflect particles
concludes: charge mass ratio q/m =1.76*10^11 c/kg
Thomson’s cathode ray experiment second follow up procedure and conclusion
procedure: uses different gases but gets the same results for negative ions
concludes: negative particles have identical outcomes therefore all substances have identical negative particles. For positive particles, different substances had different degree of deflection
what is this
plum pudding model
-dots=electrons in sphere of positive charge
milkan’s oil drop experiment conclusion
able to separate q (charge) and m (mass) for negative particles
Rutherford experiment set up:
need to know how to draw:
shoots source of alpha particles at this piece of gold foil
Rutherford experiment observations
1)most particles pass straight through
2)few particles deflected by small angles
3)very rarely (1/10000) particles deflected by wide angles
Rutherford experiment conclusion
-atom is mostly empty space with tiny nucleus where most of the mass and all the positive charge is concentrated
-negative particles are in the mostly empty space
what is this
rutherford’s model of an atom
what is one angstrom
10^-10 m
(typical size of most atoms)
relative mass of
1)proton
2)electron
3)neutron
1)1
2)1/1800
3)1
relative charge of
1)proton
2)electron
3)neutron
1)+1
2)-1
3)0
