1. Atomic Trends: Ionic Size7
14.007 O 8
16.000 F 9
18.998 Na 11
22.990 Mg 12
24.305 Al 13
26.981
1s22s22p3
1s22s22p4
1s22s22p5
1s22s22p63s1
1s22s22p63s2
1s22s22p63s23p1
+ 3e-
+ 2e-
+ 1e-
- 1e-
- 2e-
- 3e-
N3-
O2-
F1-
Na1+
Mg2+
Al3+
1s22s22p6
1s22s22p6
1s22s22p6
1s22s22p6
1s22s22p6
1s22s22p6
Ionic Radius
Isoelectronic with neon, a noble gas! (i.e. have the same electronic configuration.)
N3- Ne 10
20.18
O2-
F1-
WHY?
1s22s22p6
Na1+
Increasing nuclear charge (Z) attracts the 1s, 2s and 2p electrons more strongly  smaller ion!
Mg2+
Al3+
7p+
8p+
9p+
11p+
12p+
13p+

2. Magnetism: O2(l) N2(l) Paramagnetic: Attracted by magnetic fields
Diamagnetic: Not attracted by magnetic fields
-183.0°C (-297.3°F).
O2(l)
N2(l)
C ( F)
...contains NO unpaired electrons
...contains unpaired electrons

3. Metals, Non-metals and Metaloids
Low Ionization Energies (easy to remove e-)
High Ionization Energies (Difficult to remove e-)
High Electron Affinities (additional e- not welcome)
Low Electron Affinities (additional e- VERY welcome)

4. Why Are There Multiple Charge States
Why Are There Multiple Charge States? Finally, an answer to this “pesky” question.
Question:
What are the common ions for lead (Pb)?
Answer:
Pb2+
Pb4+ Pb 82
207.2
Why? Pb
2e- +
Pb2+
2e- +
Pb4+
[Xe] 6s2 5d10 6p2
[Xe] 6s2 5d10
[Xe] 5d10
... 6s2 electrons (“inert pair”) are removed next
...outer 6p2 electrons are removed first
pseudo-noble gas electron configuration