1. THE PERIODIC TABLE
is arranged in order of increasing number of protons.
the atomic number of an element is the number of protons in the nucleus and the number of electrons in a neutral atom.
the atomic weight increases with increasing number of protons and neutrons.
the atomic weight is the average weight of all the isotopes of that element (the average of the natural abundance x mass number).

2. THE PERIODIC TABLE
is divided into metals (left side), nonmetals (right side), and metalliods.
is arranged in rows (across) in order of increasing energy levels of valence electrons (called periods). The period number represents the energy level for that row.
is arranged in columns (down) in order of similar orbitals for the valence electrons (called groups).
The elements are represented by one or two letter symbols, which have some correlation to the element name.

3. THE PERIODIC TABLE Metals Nonmetals
Located on the left side of the periodic table
Tends to lose electrons to form cations
Has low ionization energies & electronegativity values
Forms compounds with nonmetals but not other metals
Good conduction of heat and electricity
Lustrous & malleable solids excepts Hg which is a liquid
Ductile
Nonmetals
Located on the right side of the periodic table
Tends to gain electrons to form anions
Has high ionization energies & electronegativity values
Forms compounds with both metals and nonmetals
Poor conduction of heat and electricity
Non-lustrous & brittle or gaseous
Non-ductile

4. THE PERIODIC TABLE
is divided into "blocks" which represent the orbital the electron occupies; s, p, d, and f.
is read left to right; 1s, 2s, 2p, 3s, 3p, 4s....
is arranged as representative elements (s and p block elements), transition metals (d block metals), lanthanides and actinides (f block metals).
is arranged in order of increasing energy of the subshells; the lowest energy level is always filled first.
the noble gases are unreactive since they have a completely filled shell and are the lowest in energy.

5. THE PERIODIC TABLE
Groups or families display similar physical and chemical reactivity.
the group number (roman numerals) on top represents the number of valence electrons available for that column.
common groups are:
group I = alkali metals
group II = alkaline earth metals
group VI = chalogens
group VII = halogens
group VIII = noble or inert gases

6. THE PERIODIC TABLE
demonstrates the trends in atomic properties; the periodicity of the elements.
Atomic radius,
ionization energy,
electronegativity,
magnetism
are some of the properties of atoms which can be predicted using the periodic table.

7. THE PERIODIC TABLE Atomic radius
In general, the atomic radii of the elements within a row (period) decreases from left to right due to an increase in nuclear charge whereas the radii increases down a column (group) due to the addition of electrons in higher energy levels.
decreases
increases

8. THE PERIODIC TABLE Ionization energy
This energy is required to remove an electron from an atom in the gaseous state. The first ionization energy is the amount of energy required to remove the first electron from an atom as demonstrated below:
M(g)  M(g) e-
increases
The first ionization energy generally increases across a period and decreases down a group.
decreases

9. THE PERIODIC TABLE Electronegativity
Electronegativity describes the ability of an atom to attract electrons to itself in a chemical bond. It is the attractive force that one atom has for a shared pair of electrons of a different atom in a covalent bond. Notice that the electronegativity can be related to the ionization energy and electron affinity.
increases
The electro-negativity generally increases across a period and decreases down a group.
decrease

11. THE PERIODIC TABLE Magnetism
A Paramagnetic atom is attracted to a magnetic field because it has one or more unpaired electrons.
A Diamagnetic atom is not attracted to (weakly repelled from) a magnetic field because all of the electrons are paired up.
Paramagnetic Li
________ 2s
_________ 1s
Diamagnetic He

12. PRACTICE PROBLEMS about the PERIODIC TABLE
Classify the elements as representative, transition, lanthanide, or actinide.
1. Cd 2. Te 3. Sr 4. Al 5.Gd
6. Rh 7. Cf 8. Be 9. Pd 10. O
Classify the elements by the group name:
1. Be 2. Rb 3. Xe 4. Se 5. Br
Arrange in order of increasing electronegativity.
C O Be N Sr S B
Arrange in order of increasing first ionization energy.
Arrange in order of increasing atomic radius.

13. ANSWERS
Classify the elements as representative, transition, lanthanide, or actinide.
1. Transition 2. Representative 3. representative representative
5. lanthanide transition 7. actinide representative
9. transition Representative
Classify the elements by the group name:
1. Alkaline earth 2. alkali 3. noble chalogen 5. halogen
Arrange in order of increasing electronegativity.
Sr < Be < B < S = C < N < O
Arrange in order of increasing first ionization energy.
Arrange in order of increasing atomic radius.
O < N < C < S < B < Be < Sr

14. GROUP STUDY PROBLEMS
Classify the elements as representative, transition, lanthanide, or actinide.
1. Ca 2. Tb 3. Hg 4. Es 5.Pb
Classify the elements by the group name:
1. Kr 2. I 3. Mg 4. Na 5. O
Arrange in order of increasing electronegativity, first ionization energy, & atomic radius.
Si F In Al Ba
Classify as metal, nonmetal, or metalliod:
1. Kr 2. I 3. Mg 4. Na 5. O
Classify as paramagnetic or diamagnetic: