Ch. 3 & 4 Concepts Flashcards
Thomson Model
Plum Pudding (negative particles in positive goo)
Dalton Model
Billiard Ball (indivisible sphere)
Rutherford Model
Nuclear (small dense area of positive charge w/ negative particles surrounding)
Bohr Model
Planetary (electrons orbit nucleus in energy levels)
Schrodinger Model
Quantum/Electron Cloud (electrons exist in orbitals, which are shapes where they are likely to be found)
Thomson Experiment
Cathode Ray Tube (found that atoms had charges/electrons and protons)
Rutherford Experiment
Gold Foil (shot positively charged alpha particles at gold foil, some alpha particles bounced off, found nucleus made of protons)
Millikan Experiment
Oil Drop (found charge of electron is -1)
mass defect
the amount of mass lost during the formation of a nucleus (more mass defect, more stable)
binding energy
the energy that is converted from mass during the formation of a nucleus (more binding energy, more stable)
ΔE = Δmc^2
Law of Multiple Proportions
When elements combine to make different compounds, the masses of the particles are always in ratios of small whole numbers in each compound (can have CO2 but not CO1.5)
Law of Definite Proportions
Samples of a given compound always contain the same proportion of elements by mass
20 or fewer protons in an atom
1:1 neutron to proton is most stable, too many neutrons = beta decay & not enough neutrons = electron capture/positron emission
21-82 protons in an atom
1.5:1 neutron to proton is most stable, too many neutrons = beta decay & not enough neutrons = electron capture/positron emission
83+ protons in an atom
inherently unstable, always alpha decay
Any nuclear process that gets closer to the number of protons in iron will ______
release energy
Any nuclear process that gets farther from the number of protons in iron will ______
absorb energy
critical mass
minimum amount of mass needed for a sustained chain reaction
What happens to the efficiency of a chain reaction when Uranium-238 and Uranium-235 nuclei are mixed?
the efficiency is lowered (some nuclei remain and do not undergo fission)
How does efficiency affect critical mass?
the higher the efficiency, the lower the critical mass (less mass needed to sustain a chain reaction)
Which is the most stable element?
iron
ground state
n = 1, lowest energy level ring in Bohr’s planetary model
“n” in Bohr’s model
the energy levels in Bohr’s planetary model (outer rings = higher number/more energy, inner rings = lower number/less energy)
