electron structure the quantum number the electron’s “hood”
TRANSCRIPT
Electron Structure
• The Quantum Number• The electron’s “hood”
Electron Structure• The Quantum Number• The electron’s “hood”• 3 dimensional address
Electron Structure• The Quantum Number• Attraction versus repulsion determines
region, shape of region and spin of electron• No electron can have the same 4 quantum
numbers (Pauli Exclusion Principle)
Electron Structure• The Quantum Number• Principal energy level (n)• 2 dimensional representation
Electron Structure• The Quantum Number• Principal energy level (n)• Real pattern far different- both wave and
particle
• L number (azimuthal) – shape and orbital
Electron Structure• The Quantum Number• Magnetic or m number• Spatial orientation of the orbital within
atom• Starts with negative of l and goes to
positive• E.g. l=2, m=-2,-1,0,1,2
Electron Structure• The Quantum Number• Electron-spin quantum number • AKA magnetic (ms) number
• Illustration – Helium (He) atom• Two electrons in one cloud• Opposite “spin” or magnetic qualities• + ½ (Arrow up) or -1/2 (arrow down)
Electron Structure The Quantum Number n=1, l=0,
m=01s2
s=+½,-½
Electron Structure This is the helium atom. It has 2 electrons. These are
able to share the same s orbital because of opposite spins. The "2" in "1s2" means there are 2 electrons in that orbital. "s" orbitals can only hold 2 electrons, so that's as high as you will ever see it. The 1 in "1s2" means this is the s orbital belonging to the n=1 shell. n=1, l=0, m=0
1s2, s=+½ , -½
Electron Structure
• Pauli Exclusion Principle•Each orbital can contain only one electron with each kind of spin• If two electrons are in an orbital they must have different ms values
Electron Structure
Electron StructureDiagonal fill rule
◦s levels fill first, p next , d after p and f last of all
Electron StructureHund’s Rule
Electron Configuration & The Periodic Table
Orbital Notation
Orbital Notation
Longhand notation for Li: 1s2 2s1
Shorthand notation for Li: [He]2s1
Be: [He]2s2 B: [He]2s22p1
See table 4-5 p. 90Hund’s rule example: C
Atomic Number & Mass
Atomic Mass = sum of mass of protons + mass of
neutrons
Atomic Number & Mass
http://jefflittle.edu.glogster.com/the-periodic-table/
The Periodic Table
http://jefflittle.edu.glogster.com/the-periodic-table/