cehmistry test 1 Flashcards
JJ Thompson
vacuum tube experiment
Thompson’s conclusion
- beam of light that is negatively charged
- plum pudding model
milikan
finds out that electrons are even tinyer than atoms
Ernest Rutherford
Gold foil expirement
gold foil experment
radioactive material held in a lead box,
2. alpha particle hot into the thin layer of gold foil
3. 99.99% of the shots hit right behind the gold foil
4. .01% hit to the side of the gold foil,
5. 1 in a million shots back.
6. the whole place was covered by a florescent screen
alpha particle
is a positively charged particle
Rutherford’s conclusion
- most of the atom is empty
- part of an atom must be heavy and small compared to the mass of an atom, called nucleus.
atoms are mostly empty and in the center there is a small, heavy positively charged nucleus.
isotopes
atoms with the same number of protons but different number of neutrons
atomic mass
mass of 1 atom in amu
1 mole
6.02x10^23
atoms ——–> moles
divide by 6.02x10^23
atoms <——– moles
multiply by 6.02x10^23
moles ——-> mass
multiply by molar mass
moles <—— mass
divide by molar mass
electrons
are particles but they are also waves
