1. The Periodic Table
I. Periodic Trends

2. A. Chemical Reactivity Families
Similar valence e- within a group result in similar chemical properties

3. A. Chemical Reactivity Alkali Metals Alkaline Earth Metals
Transition Metals
Halogens
Noble Gases

4. B. Other Properties Atomic Radius size of atom © 1998 LOGAL

5. C. Atomic Radius
Atomic Radius K Na Li Ar Ne

6. C. Atomic Radius Atomic Radius Increases going DOWN a group
Why? Increased number of energy levels

7. C. Atomic Radius Decreases moving from left to right across a period.
Why? Increased effective nuclear charge
Greater attraction between valence electrons and protons in the nucleus
As you move across a period, the number of valence electrons and the number of protons increases
Therefore, there is a stronger attraction!

8. D. Ionization Energy First Ionization Energy
Energy required to remove one e- from an atom.
H(g) → H+(g) + e ∆Ho = kJ/mol
He(g) → He+(g) + e- ∆Ho = kJ/mol
Li(g) → Li+(g) + e- ∆Ho = kJ/mol

9. D. Ionization Energy
First Ionization Energy He Ne Ar Li Na K

10. E. Ionization Energy First Ionization Energy
Increases UP and to the RIGHT
Why? Moving up a column there is a stronger attraction between the electrons and the nucleus
Moving across a period, there is also increased attraction between the electrons and the nucleus because decreased atomic size

11. D. Ionization Energy Successive Ionization Energies
Large jump in I.E. occurs when a CORE e- is removed.
Mg 1st I.E kJ
2nd I.E. 1,445 kJ
Core e- 3rd I.E. 7,730 kJ

12. E. Ionic Radius Ionic Radius Cations (+) lose e- smaller Anions (–)
gain e-
larger
© 2002 Prentice-Hall, Inc.

13. F. Electronegativity
*The measure of how strongly an atom attracts another atom’s electrons
Increases from left to right (except for noble gases)
Increases as you move up a group

14. Examples
Which atom has the larger radius?
Be or Ba
Ca or Br Ba Ca

15. Examples
Which atom has the higher 1st I.E.?
N or Bi
Ba or Ne N Ne

16. S or S2- Al or Al3+ S2- Al Examples
Which particle has the larger radius?
S or S2-
Al or Al3+
S2- Al