1. Periodic Table Metals Nonmetals Main Group Noble gases
Transition metals
Lanthanides & Actinides

2. Metals

3. Nonmetals

4. Main Group Elements

5. Noble Gases

6. Transition Metals

7. Lanthanides and Actinides

8. Ionic Charges of Main Group1 II
III IV V VI
VII

9. Main Group Ions
Group I and II: cations that correspond to group number
Na+, Mg2+, Sr2+
Group III: Al (Ga): Group number: Al3+
Group IV: no monatomic ions
Group V, VI, VII: anions that are 8 – group number: N3-, S2-, Br–

10. 1 – Predict the charges on the ions formed from the following Main Group atomsMg Cl F N P K Ba

11. 1 – Predict the charges on the ions formed from the following Main Group atomsMg Cl F O P K Ba
Mg2+
Cl– F–
O2–
P3– K+
Ba2+

12. Periodic Table Law versus Theory Scientific Law Empirical observation
No known exceptions
Often a relationship between properties

13. Periodic Table Scientific Theory Periodic Table
Principles that explain observations associated w/ laws
Testable and tested
Periodic Table
Mendeleev & Meyer
Empirical observations
Atomic Theory came much later

14. Periodic Properties: Atomic Size
Atoms are not billiard balls.
Radial Electron Density (Atomic Radius)
Effective Nuclear Charge, Zeff
Z = number of protons
Zeff < Z
Shielding or screening by inner shell electrons

15. Atomic Radius Z+ Nuclear charge is screened by inner shell electrons
Zeff < Z Z+
n=1
n=2
n=3

16. Atomic Radius
“Same” shell electrons do not screen as well as inner shell electrons.
Zeff  as you fill a shell (move across row of periodic table)
Na Mg Al Si P S Cl Ar
Increasing Z (+1)
Screening < 1
Zeff 
Zeff = Z – S

17. Atomic Radius Atomic radius  as you move across row
Atomic radius  as you move down column
Size decreases
Size increases

18. Problem 2
Arrange each of the following groups of atoms in order of increasing size:
Cl, Mg, Si
Ge, Pb, C

19. Problem 2
Cl < Si < Mg
C < Ge < Pb

20. Ionic Size in an Isoelectronic Series
Isoelectronic Series: N3– O2– F– Ne Na+ Mg2+ Al3+
Size decreases
Same electron configuration
Increasing Z

21. Periodic Properties: Ionization Energy
M + energy  M+ + e–
Ionization energy, In
M+ + energy  M2+ + e– I2
As Zeff , In 
Photoelectric effect:
I1 = Eho

22. Ionization Energy
Ionization Energy Increases

23. Problem 3
Arrange the following groups of atoms in order of increasing ionization energy.
Cr, N, Rb, F
Ar, In, P, Ba,

24. Problem 3
Rb < Cr < N < F
Ba < In < P < Ar

25. Ionization Energies Atom I1 I2 I3 I4 I5 I6 I7 Na Mg Al Si P 496 4560
6912
9544
13,353
16,610
20,115 Mg
738
1450
7730
10,540
13,630
17,995
21,704 Al
578
1820
2750
11,600
14,800
18,400
23,300 Si
786
1580
3230
4360
16,100
19,800
23,800 P
1012
1900
2910
4960
6270
22,200
25,400

26. Other Periodic Trends
Physical properties
Ion formation
Reactivity

27. Other Periodic Trends Alkali metals Form +1 ions
Very reactive with O2, water
Gray, soft metals
Always found in compound form

28. Other Periodic Trends
Alkaline earths
Form +2 ions
Less reactive

29. Other Periodic Trends Halogens Form –1 ions, very negative
electron affinities
Very reactive with metals to form MnXy

30. Other Periodic Trends Noble Gases Monatomic Very unreactive (Xe, Kr)
Large I1