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Chemistry Notes on Atomic Structure, Electron Configuration, Periodic Trends and Bonding

Electron Configuration Table

Click to view full size!

Click to view full size!

Electron Configuration

Paramagnetic - elements that have unpaired electrons

Dimagnetic - elements that do not have unpaired electrons

Pauli Exclusion Principle - No 2 electrons can have identical quantum numbers and will be found in opposite spins as marked by a (-1/2 and 1/2)

Degenerate orbitals - orbitals with the same principal energy levels (n) have the same amount of energy because there is no electron-electron repultion, only proton-electron attraction and kinetic energy motion.

Principal Energy Levels(n)

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7

Sublevels (L)

  • s
  • sp
  • spd
  • spdf
  • spdf
  • spdf
  • spdf

Excited Electron States


Wavelength and Photons

When you excite an electron (give it energy) it moves to a higher energy level. When it returns to the ground it gives off wave energy (some type of light). 

  • Speed of light: λv=C
  • Plank's Constant: ΔE=hv
  • v=hertz/frequency (cycles per second)
  • Energy=mass x the speed of light (C0
  • deBroglie's Equation: λ=h/(m)(v)

Periodic Table Trends

  • Ionization energy - decreases down a group, increases across a period
  • Electronegativity - decreases down a group, increases across a period
  • Atomic Radius - increases down a group, decreases across a period

Bonding (VSEPER)

***The electrons ALWAYS want to be as far apart as possible!***

Number of electron pairs and VSEPER (Valance Shell Electron Pair Repulsion) arrangement.

  • 2 pairs = linear
  • 3 pairs = Trigonal planar
  • 4 pairs = tetrahedral
  • 5 pairs = Trigonal bipyramidal
  • 6 pairs = Octahedral
Click to view full size!  Steric number = number of electron pairs

Click to view full size! Steric number = number of electron pairs

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Ochi Raphael on February 20, 2011:

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