Chemistry Quantum Numbers

Heisenberg’s Uncertainty Principle

You can’t know the exact position of an electron

Orbital

A 3D region in the space around the nucleus in which the propability of finding an electron is maximum

Quantum numbers

How you can find an electron

Principle Quantum Number (n)

energy level (relative distance from nucleus

Angular Momentum Quantum Number (L)

Shape of the orbital (S, P, D, or F)

Magnetic Quantum Number (M)

Orientation (which orbital)

Spin Quantum Number (S)

Gives spin, up or down (+1/2, -1/2)

Aufbau Principle

electrons go into lowest energy level available

Pauli Exclusion Principle

2 electrons in same orbital must have different spins

Hund’s rule

One electron in all orbitals before you start pairing

Left side of the periodic table

S

Right side of the periodic table

P

Middle of the Periodic table

D

Bottom of the Periodic table

F

Orbital notation

Energy level, sublevel, lines for orbitals, arrows for spin

Electron Configuration

Energy level, sublevel, number of electrons as an exponent

Copper and chromium

Doesn’t follow Hund’s rule