Quiz 2 Cram Flashcards
Rutherford experiment
- started with positively charged alpha particles
- shot them through gold foil
- used a fluorescent screen to detect it
Rutherford experiment observations
- most of the radiation went through the gold foil
- there’s space around the atom
- some radiation rays went different directions at an angle
- some parts of the gold foil have a positive charge so it would deflect the ray that was near it
- some deflected back
- positive charge would bounce the ray back if it is close to the positive charge in the gold foil
Progressive Atomic Theory
- Atom is composed of 3 types of subatomic particles
- protons, neutrons, electrons
protons
positive charge, found in the nucleus (mass: 1)
neutrons
found in the nucleus (mass: 1)
electrons
negatively charged found floating(orbit) around the nucleus
the atomic number =
number of protons
number of protons =
number of electrons
Isotopes
atoms of the same element but with different masses (various versions of an element)
- different number of neutrons but same number of protons
- have the same atomic number because the number of protons stay the same
- you can predict the same amount of electrons in a neutral atom bc they are the same to protons
neutron calculation =
mass # - # of protons
Mass number =
number of protons + number of neutrons
cathode
negative
anode
positive
Dalton’s Atomic Theory
- Each element is composed of extremely small particles called atoms
- All atoms of a given element are identical; but one elements atoms are different from another element’s atoms
- Atoms of one element cannot change into toms of a different element; atoms can not be created or destroyed
- compounds are formed when atoms of more than one element combine
