1. History of Periodic Table and Periodicity

2. Mendeleev organized the elements based on their properties and developed the first periodic table
He left blanks based on chemical properties and elements were later discovered to fill in the blanks
Later it was discovered that the periodic table became “more correct” if the elements were arranged by atomic number

3. Alkali metals, alkaline earth metals, transition metals, metalloid, halogens, noble gases, lanthanides, actinides
Properties of elements: conductors, reactivity

4. Periodicity
Must know 3 periodic trends and why that trend occurs

5. Atomic Radii one half the distance between bonded atoms
Decreases to the right on the periodic table due to the increasing positive charge of the nucleus
Increases down the periodic table due to adding new energy levels
There are a few exceptions due to electron configurations

6. Ionization Energy
The energy required to remove one electron from a neutral atom
Increases to the right due to increasing nuclear charge and decreasing atomic radii
Decreases down due to a larger atomic radii
Second ionization energy is always higher than first
Harder to remove an electron from a positive ion

7. Electronegativity
A measure of the ability of an atom to attract electrons
Increases to the right
Increases up
Due to atomic radii, nuclear charge, and electron configuration
F is the most electronegative element
Noble gases have 0 electronegativity

8. Choose the element with the larger atomic radius
Mg Cl
S Se
Ni Fe
S Br

9. Choose the element with the higher electronegativity
Br I
Al Si
Mg Ca
P Ar

10. Choose the element with the Lower ionization energy
P S
Ar Mg
Ca Sr
Cu Ag

11. Ne, P, Fe, Ca, Cs, Al, Zn
Arrange the above elements in order of increasing ionization energy
Arrange the elements above in order of increasing atomic radius
Arrange the elements above in order of decreasing electronegativity