Periodic Table Notes
Periodic Law – properties of the
elements are a periodic function
of their atomic number
The moon’s phases
and magazine
subscriptions are
also periodic…
Periods – horizontal arrangements
of atoms, with reoccurring
similarity of chemical (and often
physical) properties
Periods are
numbered
1-7 (but
more could
be coming)
Groups– elements in the periodic
table arranged vertically and have
very similar chemical (and often
physical) properties
Groups are
numbered 1-18,
or 1-8 A for the
representative
(tall) groups and
1-8 B for the
transition
(middle) groups
1. Atomic Radius – (size)
a. increases as you move top to
bottom within a group or family
(increases because the energy
levels increase → high energy
means further from the nucleus)
1. Atomic Radius – (size)
a. increases as you move top to
bottom within a group or family
b. decreases as you move left to
right because of effective nuclear
charge → more protons in the
nucleus to attract the electrons
closer
2. Effective Nuclear Charge (ENC)
– pull of the nucleus on the
valence energy level electrons
(outer energy level electrons)
a. increases left to right
3. Ionization Energy (IE) – energy
required to remove an electron
from a gaseous atom
a. increases bottom to top and left
to right
4. Electron Affinity (EA) – energy
released when an electron is
added to a gaseous atom
a. increases bottom to top and left
to right
5. Electronegativity – (EN) –
measure of an atom’s pull on
another atom’s electrons
a. increases bottom to top and left
to right
6. Shielding – layers of electrons
that protect valence electrons
from the pull of the nucleus
a. increases top to bottom and
b. constant left to right
7. metallic character – ease of
losing an electron
a. increases top to bottom and
right to left
8. nonmetallic character – ease of
gaining an electron
a. increases bottom to top and left
to right
ions – charged particles
9. cations – postive ion formed
from an atom losing an electron
a. the Ionic radius is always
smaller than the parent atom
because of fewer energy levels
10. Anions – negative ion formed
from an atom gaining an electron
a. the Ionic radius is always larger
than the parent atom because of
electron repulsion
Atomic Radius
Ionization Energy, Electron Affinity, Electronegativity
Effective Nuclear Charge
Shielding
Metallic Character
Nonmetallic Character
Periodic Trends Foldable
• Make a flip book with 3
pages
• Title it “Periodic Trends”
• Label each tab
– Atomic Radius
– Ionic Radius
– Electronegativity
– Ionization Energy
– Comparisons
• For each tab (except
comparisions), draw an
outline of a periodic table
• Mark on the table the
biggest and smallest
• For each trend, compare
two elements
• For example: Francium has
a larger atomic radius than
Fluorine.
*You can’t use my example.
*write a complete sentence
Comparisons Tab
• For each trend, compare two elements
• For example: Francium has a larger
atomic radius than Fluorine.
*You can’t use my example.
*write a complete sentence