1. Mendeleev
Arranged the 70 known elements at the time in columns in order of increasing atomic mass. He then arranged the columns so that the elements with the most similarities were side by side.
Created the first Periodic Table.

2. Mendeleev’s First Periodic Table

3. Periodic Table: an arrangement of the elements according to the similarities in their properties
Mendeleev was even able to predict the physical and chemical properties of the missing elements. (When these elements were discovered, they were found to have properties similar to those predicted)

4. Moseley
Moseley later arranged the elements in a table by order of atomic number instead of atomic mass

5. The Periodic Table Periods: horizontal rows are called periods
There are seven periods
The properties within a period change as you move across it from element to element
If you move from one period to the next, the properties within the period repeat
All elements in a period have the same # of atomic orbitals
Ex. First period (1 orbital)
Second period (2 orbitals)

6. The Periodic Table Groups or Families:
Vertical columns of elements in the PT
The elements in any family of the PT have similar physical and chemical properties
Have the same number of electrons in their outer orbitals (valence electrons)
Hydrogen has characteristics of both group 1 and 7
Helium needs only two electrons in its outer shell to be filled (happy).
Families have specific names associated with them because they have similar physical and chemical properties

8. 75% of Elements are Classified as Metals
Properties of metals:
conduct electricity
high luster
ductile (able to be drawn into wires)
malleable (able to be beaten into thin sheets
elements on the left and center of the PT are metals

9. Groups or Families: divided into 8 groups

11. no images of Francium available
Group 1: Alkali Metals Li
very reactive
never found free in nature
react readily with water
shiny, light in weight Na K Rb Fr
no images of Francium available Cs

12. Group 2: Alkaline Earth Metals
reacts with oxygen
not as reactive as Group 1, makes bonds very easily
Ca Calcium

13. Group 3:
Boron group, made of metals and metalloids
Group 4:
Carbon group, made of Metals and Nonmetals
Group 5:
Nitrogen group, elements form an oxygen or sulfur compound
Group 6:
Oxygen group, Nonmetals

14. Group 7: Halogens
elements combine violently with alkali metals to form salts
Halogens mean “salt-forming”
Highly reactive
7 electrons in outer shell, only need one to be happy

15. Group 8: Noble Gases
have full outer shells with 8 electrons (except for He)
least reactive group
not very abundant
Neon in advertisement signs
Argon light bulbs
Helium balloons
Xenon used in headlamps (ultra bright-blue)

16. Metalloids:
Stair step line that distinguishes metals from non-metals. Drawn from between Boron & Aluminum to the border of Polonium & Astatine
Boron
Silicon
Germanium
Arsenic
Antimony
Tellurium
Polonium

17. Transition Metals:
All elements between Group 2 and Group 3, including the inner transition metals (lanthanide & actinide series)
Able to put more than 8 electrons in their next to last shell
Can use the two outermost orbitals to bond with other elements
Actinide series are radioactive and some cannot be found in nature
Lanthanide series can be found naturally on earth

18. Transition Metals

19. Periodic Table Review
What criteria did Mendeleev use to construct his PT?
arranged elements by order of atomic number
arranged elements by order of atomic mass
What criteria did Moseley use to reconstruct the PT?
arranged elements by order of atomic number
arranged elements by order of atomic mass

20. Review A period on the Periodic Table:
is represented by vertical columns of elements which have similar physical properties and chemical properties
is represented by horizontal rows of elements and the properties of the elements change as you move from element to element

21. Review A Family/Group on the Periodic Table:
is represented by vertical columns of elements which have similar physical properties and chemical properties
is represented by horizontal rows of elements and the properties of the
elements change as you move from element to element

22. Review Identify each element as a metal, metalloid, or nonmetal gold
silicon
manganese
sulfur
barium
Metal
Metalloid
Nonmetal

23. Review
Pick two elements that have properties similar to those of the element calcium Zn Mg Cr Sr