1. Quantum Theory
Electrons!

2. Let there be Light!
Light behaves as a wave and a particle. (reflection, refraction, diffraction etc, but also emission of photons)
Electrons have the same properties.
Quantum Theory – describes the wave properties of electrons and other small particles mathematically.

3. Heisenberg Uncertainty Principle
One can’t determine both the position and the velocity of an electron or any other particle.

4. Schrodinger Wave Equation
Mathematical equation that describes how an electron behaves. Describes properties such as position, momentum(mass times velocity), energy, etc. Predict the first three quantum numbers.

5. Atomic Orbitals
An orbital is the 3D space around a nucleus that predicts the probably location of an electron.
Quantum numbers – specifies the properties of atomic orbitals and the properties of electrons in those orbitals.

6. Principal Quantum Number
The main energy level occupied by the electron. Described by n, positive integers (1, 2, 3, etc). Higher values – more energy Give it enough energy and the electron will leave the atom.

7. Angular momentum quantum number
Indicates the shape of the orbital.
Shown by l, and given by 0 and less than or equal to n-1.
Ex. n=2, l= 0 or 1
l letter
0 s
1 p
2 d
3 f

9. Magnetic Quantum Number
Indicates the orientation of an orbital around the nucleus.
Given by m, all whole numbers from –l to l.
l=1 can have m of -1, 0, 1

10. Spin Quantum Number Can only be +1/2 or -1/2
The fundamental spin state of an electron, which can only exist in opposite states.

11. For review:
n can have whole number values: 1, 2, 3, ...
For every value of n, ℓ can have integer values from 0 to (n-1)
m can have any whole number value, including zero, from -ℓ to +ℓ
s can be either +½ or -½

12. What is the electron configuaration for sodium?
For argon?

13. Electron Configuration