Transcript Chapter 5

Chapter 5
The Periodic Law
I. History of the Periodic Table
A. By 1860, more than 60 elements had
been discovered.
1. they needed a method to determine
properties and atomic mass
2. 1860, the First International
Congress of Chemist met in
Germany to settle some of these
issues
B. Mendeleev and Chemical Periodicity
1. when he arranged the elements in
order of increasing atomic mass,
similarities in their chemical
properties appeared at regular
intervals
2. periodic –
3. I after Te because of properties
4. several empty spaces left, these
elements were discovered later
5. discoverer of the periodic law
C. Moseley and the Periodic Law
1. 1911, English scientist, Henry
Moseley noticed the elements fit
into patterns better when arranged
by increasing nuclear charge
2. periodic law –
D. The Modern Periodic Table
1. periodic table –
2. Noble gases
a. discovered by –
b. description –
3. Lanthanides –
4. Actinides –
5. Periodicity -
II. Electron Configuration and the
Periodic Table
A. generally the electron configuation of an
atom’s highest occupied E level
governs the atom’s chemical properties
B. Periods and Block of the Periodic Table
1. period –
2. Table 1, page 138
3. block -
C. s-block Elements: Groups 1 & 2
1. chemically reactive metals
2. group 1 more reactive than group 2
3. group 1 = alkali metals
a.
b.
c
4. group 2 = alkaline earth metals
a.
b.
c.
D. Hydrogen & Helium
1. Hydrogen –
2. Helium –
E. d-block Elements: Groups 3 -12
1. transition elements –
2. least reactive –
F. p-block Elements: Groups 13-18
1. main group elements –
2. halogens -
3. metalloids –
4. metals of p-block
G. f-block Elements: Lanthanides &
Actinides
1. Lanthanides –
2. Actinides -
III. Electron Configuration and
Periodic Properties
A. Atomic Radii –
1. period trend2. group trend –
3. d-Block properties –
4. f-Block properties -
B. Ionization Energy
1. ion –
2. ionization –
3. ionization E –
a. period trend –
b. group trend –
c. d-Block properties –
d. f-Block properties -
4. Removing electrons from positive
ions
a. the energies for the removal of
additional electrons from an
atom are called the 2nd
ionization E , 3rd ionization E,
etc.
b. each successive electron
removed from an ion feels
an increasingly stronger
effective nuclear charge
C, Electron Affinity –
1. period trends –
2. group trends –
D. Ionic Radii
1. cation –
2. anion –
3. period trends –
4. group trends5. d – Block properties –
6. f-Block properties -
E. Valence electrons –
F. Electronegativity –
1. period trends –
2. group trends –
3. d – Block properties –
4. f-Block properties -