1. Chemical Periodicity
Chapter 14

2. Periodic Table Mendeleev (1871) Modern Periodic Table
Most successful in organizing the periodic table
Arranged the periodic table by order of increasing atomic mass
Modern Periodic Table
Arranged in order of increasing ATOMIC NUMBER!!!

3. Classifying Elements by Electron Configuration
ELECTRON plays the most important role in determining the physical and chemical properties of an element

4. 4 Categories According to Electron Configuration
NOBLE GASES-outermost s & p sublevels filled
Group 0 or 8
Inert gases

5. REPRESENTATIVE ELEMENTS
-outermost s or p sublevel is only partially filled
aka “main block”
Group 1A = alkali metals
Group 2A = alkaline earth metals
Group 7A = nonmetallic elements, halogens

6. Valence Electrons
VALENCE ELECTRONS-the # of electrons in the outermost energy level
Group # equals the # of electrons in the outermost energy level
Li 1s22s1
Na 1s22s22p63s1
K 1s22s22p63s23p64s1

7. TRANSITION METALS-metallic elements in which the outermost s sublevel and nearby d sublevel contain electrons
INNER TRANSITION METALS-metallic elements in which the outermost s sublevel and nearby f sublevel generally contain electrons

8. Periodic Trends ATOMIC SIZE (radii)
Shielding effect: other electrons screen/shield a given electron from some of the nuclear charge
decreases
Inc

9. Relative atomic sizes for selected atoms.

10. The ions formed by selected members of groups 1, 2, 3, 6, and 7.

11. IONIC SIZE
Same trend as atomic radii when comparing same type of ion (cation or anion)
Cations are smaller than neutral atoms
Anions are larger than neutral atoms

12. Relative sizes of some ions and their parent atoms.

13. IONIZATION ENERGY The energy required to remove an electron increases
DIE

14. ELECTRONEGATIVITY
The tendency for an atom to attract electrons to itself when it is chemically combined with another element.
FLUORINE is the most electronegative element
increases F
dec

15. Electronegativity Values