1. Chp 5-1 Shell Models 1st shell (energy level): only 2 electrons
2nd shell (energy level): up to 10 electrons
3rd shell (energy level): up to 18 electrons (10 in d-orbital, 8 total in s- and p-orbital)

2. Chp 5-1 Octet Rule Most atoms want to have 8 valence electrons
They want to have an electron configuration of a noble gas (be stable)
They will do this in the easiest way possible

3. Ions Ion: a charged atom (it has gained/lost electrons)
Cations: positively charged atoms (lost electrons)
Metals e.g. Na -> Na+ + electron
Anions: negatively charged atoms (gained electrons)
Nonmetals e.g. Cl + electron -> Cl-

4. Ions When these ions form, the outermost s- and p-orbitals are filled
Group 1, 2 and 13 will lose electrons and become positively charged (cation)
Group 15, 16, and 17 will gain electrons and become negatively charged (anion)
They gain or lose electrons based on the quickest/easiest way

5. Ions
How would each of the following react to reach a noble-gas configuration?
1. Iodine answer: gain 1 electron
2. Nitrogen
3. Krypton
4. Magnesium

6. What will be the charge of these elements if they have a noble gas configuration?
Nitrogen = N-3
Aluminum
Bromine
Potassium

7. Draw these