1. 5-2: Electron Configuration and the Periodic Table
Objectives:
Describe the relationship between electrons in sublevels and the length of the each period of the periodic table
Locate and name the four blocks of the periodic table. Explain the reasons for the three names.
Discuss the relationship between group configurations and group numbers
Describe the locations in the periodic table and the general properties of the alkali metals, the alkaline-earth metals, the halogens, and the noble gases.

2. … Remember?
Electron configuration?
Four types of sublevels?

3. Periods and Blocks of the Periodic Table
Group: a vertical column of elements in the periodic table
Tells how many electrons are in the atom’s outer shell (valence electrons)
Period: a horizontal row of elements in the periodic table
Length of each period is determined by the number of electrons that occupy the energy sublevels being filled

4. Period of an element can be determined from the element’s electron configuration
Periodic table can be divided into four sublevel blocks based on the electron configuration of elements – s, p, d, and f blocks

5. The s-Block Elements: Groups 1 and 2
Elements of the s-block are chemically reactive metals
Elements of Group 1:
Outermost energy level contains a single s electron
Alkali metals: elements of Group 1 of the periodic table (Li, Na, K, Rb, Ce, Fr)
Properties:
Silvery appearance and soft enough to cut with a knife (in its pure state)
Highly reactive
Combine strongly with most nonmetals

6. Elements of Group 2:
Outermost energy level contains a pair (2) electrons
Alkaline-earth metals: elements of Group 2 of the periodic table (Be, Mg, Ca, Sr, Ba, Ra)
Properties:
Metals are harder, denser, and stronger than alkali metals
Higher melting points
Highly reactive
Hydrogen and helium do not share the same properties of Group 1 and 2, respectively

7. The d-Block Elements: Group 3-12
Transition metals: metals with typical metallic properties in the d-block of the periodic table
Properties:
Good conductors of electricity
High luster
Less reactive than alkali and alkaline-earth metals
Some so unreactive they do not form compounds easily

8. The p-Block Elements: Groups 13-18
Properties of the elements of the p-block vary greatly
Includes:
all of the nonmetals except hydrogen and helium
all six of the metalloids (B, Si, Ge, As, Sb, Te)
the halogens
the noble gases

9. Metalloids (semiconducting metals)
Halogens: the elements of Group 17 (fluorine, chlorine, bromine, iodine, and astatine)
The most reactive nonmetals
React vigorously with most metals to form salts
Metalloids (semiconducting metals)
mostly brittle solids with some properties of metals and some of nonmetals
Metals of the p-block
Generally harder and denser than the s-block alkaline-earth metals, but softer and less dense than the d-block metals
Sufficiently reactive to be found in nature only in the form of compounds
Stable in the presence of air

10. Main-group elements: elements of the p- block together with elements of the s-block

11. The f-Block Elements: Lanthanides & Actinides
Electrons fill the 4f sublevel
Lanthanides are shiny metals similar to the Group 2 alkaline-earth metals
Actinides are all radioactive
The first 4 have been found naturally and the remaining are known lab-made elements

12. 4-shutter foldable
s p
d f

13. s p d f Alkaline-earth metals Noble gases Alkali metals Metalloids
Transition metals
Metalloids
Halogens
Lanthanides
Actinides f