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Electron
Mass = 0.00055 amu
Charge = -1.6 x 10^-19 coulombs
Proton
Mass = 1.00727 amu
Charge = +1.6 x 10^-19 coulombs
Neutron
Mass = 1.00866 amu
Charge = no charge (neutral)
Avagadro''s Number
6.0228 x 10^23 atoms equals 1 mole
[IMGPATH:]/sdcard/StudyDroid/Atomic Structure-5-true.jpg
X = atom symbol
A = mass number
Z = atomic number
A - Z =N = neutron number
Iso.... Definitions
Isotope --> same number of protons
Isotone --> same number of neutrons
Isobars --> same A (mass number)
Isomers --> same atom different energy state
Energy Units
1 eV = 1.6 x 10^-19 joules
E = mc^2
1 amu = 931 MeV
c = 3.0 x 10^8 m/s
Mass Defect & Binding Energy
Mass defect = mass of individual components - actual mass of atom

Binding Energy = energy equivalent of mass defect / energy required to break an atom apart
Four Forces in Nature
Weakest -------> Strongest

1) gravitational force
2) electrostatic force
3) weak force
4) nuclear force
Fission vs. Fusion
Fission - break apart (heavy atoms)

Fussion - combine together (lighter atoms)
Electron Binding Energy
Higher Z
Higher positive nucleus charge
Greater electron BE
Electron Cascade
Inner electron vacancy results in multiple electrons falling eac to fill a lower energy orbital

Process releases a range of characteristic EM radiation with energy E = BE0 - BE1
--> large changd in E produces x-rays (fluorescence x-rays)
--> lower change in E produces EM too low to be called x-rays
THEREFORE higher Z atoms (greater BE changes) produce more characterisitc x-rays
Auger Electrons
Alternate to EM radiation

Energy released transferred to a different electron further from the nucleus - electron ejected with E = E0 - BE1
Fluorscence Yield
w = (# of characteristic EM) / (# electron vacancies)

More Auger electrons from lower Z
--> w increases with Z
Stable Atoms
Light atoms ==> N ~ P
Heavier Atoms ==> N > P
[IMGPATH:]/sdcard/StudyDroid/Atomic Structure-18-true.jpg
No stable form of atom for Z > 83
Unstable Nuclei
Move towards stability by emission of particles and EM radiation

Release energy in the process resulting in increased BE
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