1. The Periodic Table

2. What is the Periodic Table?
It is an organizational system for elements.
Picture from

3. Who created it?
By 1860 about 60 elements were known and a method was needed for organization. 
Mendeleev arranged the elements by atomic mass.

4. Mendeleev’s Table
Mendeleev predicted the properties of elements not yet discovered (?’s)

5. So how is it arranged now? And why is it a big deal anyway???
Mendeleev’s table was good, but it did have some mistakes.
The periodic table was later arranged by atomic number, or the number of protons. This fixed Mendeleev’s errors.
The arrangement of the elements in the Periodic Table keeps us from having to memorize facts about all 119 elements!

6. Periods Each row is called a “period”
The elements in each period have the same number of shells
1st Period = 1 Shell
2nd Period = 2 Shells
3rd Period = 3 Shells
4th Period = 4 Shells

7. Groups Group 8 = 8 electrons Group 1 = 1 electron
Except for He, it has 2 electrons
Group 2 = 2 electrons
Each column is called a “group”
3, 4, 5, 6, 7
Each element in a group has the same number of valence electrons.

8. Transition Metals
Transition Metals have slightly different rules for shells and valence electrons.
This is something you will learn about in High School Chemistry.

9. Determine the number of shells and the number of valence electrons for:
Carbon - C
2nd Period = 2 shells
4th Group =
4 valence
electrons

10. Determine the number of shells and the number of valence electrons for:
Sodium - Na
3rd Period = 3 shells
1st Group =
1 valence
electron

11. Write your answers on your notes.Ne
Name the element.
Number of shells?
# of Valence electrons?

12. Write your answers on your notes.Ne
Name the element.
Number of shells?
# of Valence electrons?
Neon
2nd Period = 2 shells
8th Group = 8 valence
electrons

13. Valence Electrons
Explain what happens to the number of valence electrons as you move from LEFT TO RIGHT in the periodic table.
What is true about valence electrons of stable elements? (example - noble gases)
DISCUSS WITH YOUR ELBOW PARTNER and write your answers for #4 and #5 on your notes.

14. Valence Electrons
Explain what happens to the number of valence electrons as you move from LEFT TO RIGHT in the periodic table.
What is true about valence electrons of stable elements? (example - noble gases)

15. How metallic an element is
Explain what happens to how metallic elements are as you move from LEFT TO RIGHT in the periodic table.
Hint: Where are the metals compared to the non-metals?
DISCUSS WITH YOUR ELBOW PARTNER and write your answers for #6 on your notes.

17. How metallic an element is
Explain what happens to how metallic elements are as you move from LEFT TO RIGHT in the periodic table.

18. Reactivity
Explain what happens to the number of electron shells as you move DOWN the periodic table? Relate this to how ‘reactive’ the elements are.
Hint: The farther away from the nucleus electrons are, the more energy they have.
DISCUSS WITH YOUR ELBOW PARTNER and write your answers on your notes for #7

19. Reactivity
Explain what happens to the number of electron shells as you move DOWN the periodic table? Relate this to how ‘reactive’ the elements are.
Hint: The farther away from the nucleus electrons are, the more energy they have.

20. Let’s re-cap Discuss with your elbow partners:
What are the patterns as you move ACROSS?
What is the patterns as you move DOWN?

21. Sodium demo Discuss with your elbow partners:
How many valence electrons does sodium have?
How many electron shells does it have?

22. Sodium demo SAFETY READY: glasses, aprons
Stand BEHIND the picnic tables
QUIET IN THE HALLS
Make quantitative & qualitative observations about:
The appearance of pure sodium (characteristics of metals)
What happens when it is added to water

23. Sodium demo Write quantitative & qualitative observations about:
The appearance of pure sodium (characteristics of metals)
What happens when it is added to water

24. Sodium demo - explained
alkali metal - shiny, malleable/ductile
1 valence electron – really wants to lose  chops water apart
2Na H20  NaOH H2
Sodium + water  sodium hydroxide hydrogen gas
Exothermic reaction – releases heat  heat + H2 + O2 = BOOM
Sodium gets hot and turns orange (characteristic color)

25. Reactivity
Explain what happens to the number of orbitals (electron shells) as you move DOWN the periodic table? Relate this to how ‘reactive’ the elements are.
Mute briefly at 0:50

26. Check for Understanding
What properties change as you move ACROSS the periods (rows)?
What properties change as you move DOWN the groups (columns)?
What is similar between elements in the same group?
The number of valence electrons _____________ as you move from left to right.
Elements become _____________ metallic as you move from left to right.
 As you move down, electron shells are _____________ which means greater _____________ in the valence electrons.
Elements become _____________ reactive as you move down a group.
Elements in the same group share similar _____________ and _____________ properties because of their same number of valence electrons.

27. More about the P.T. (p. 309)
What do you know about metals because of their location on the Periodic Table? (in terms of valence electrons)
What do you know about nonmetals because of their location on the Periodic Table? (in terms of valence electrons)
What do atoms do if they do not have full valence shells?
Discuss with your ELBOW PARTNER and write your answers for #12-14

28. More about the P.T. (p. 309) They have FEW valence electrons
What do you know about metals because of their location on the Periodic Table? (in terms of valence electrons)
What do you know about nonmetals because of their location on the Periodic Table? (in terms of valence electrons)
What do atoms do if they do not have full valence shells?
They have FEW valence electrons
They have ALMOST FULL/FULL outer shells
Metals tend to LOSE electrons while nonmetals tend to GAIN electrons.

29. Set timer for 7 minutes to allow students to independently read and fill in chart. Then review using next 3 slides.

30. LEFT SIDE of zigzag line
Iron (skillet)
Copper (wires)
Alumimum (foil)
Most are solids

31. LEFT SIDE of zigzag line
Iron (skillet)
Copper (wires)
Alumimum (foil)
Most are solids X
RIGHT SIDE of zigzag line X
Carbon (pencil)
Sulfur
Nitrogen
Oxygen X X X
Brittle; Most are gases

32. LEFT SIDE of zigzag line
Iron (skillet)
Copper (wires)
Alumimum (foil)
Most are solids X
RIGHT SIDE of zigzag line X
Carbon (pencil)
Sulfur
Nitrogen
Oxygen X X X
Semi-conductors
On the border of the ZIGZAG LINE
Silicon, Germanium, Tellurium
(Found in electronics) X
Properties of both METALS & NONMETALS
Brittle X

33. Other than periods and groups, the table is divided into families.
From

34. ALKALI METALS Very reactive React violently to water
Rarely found freely in nature (usually join with other atoms to form compounds)
From

35. ALKALINE EARTH METALS Very reactive
Not found freely in nature (always found as compounds)
From

36. TRANSITION METALS
Include many metals used in everyday things: iron, nickel, copper, silver, gold
some produce a magnetic field
From

37. RARE EARTH ELEMENTS Lanthanides & Actinides many are man-made
From

38. OTHER METALS have a high density examples: aluminum, tin, lead
From

39. METALLOIDS Have properties of both metals and non-metals
Some of the metalloids are semi-conductors (carry electrical charge under special conditions).
Used in electronics
From

40. NON-METALS Poor conductors of electricity and heat (insulators)
Brittle
Dull (not shiny)
From

41. HALOGENS "halogen" means "salt-former“
Very reactive – want to gain 1 electron
Exist in all three states of matter
From

42. NOBLE GASES Usually found by themselves (rarely form compounds)
Stable (Full outer shells)
From

43. OUTLINE in marker

45. Focus Paragraph Ideas
Metals are found on the (LEFT/RIGHT) side of the Periodic Table and nonmetals are found on the (LEFT/RIGHT) side. Metalloids are found…
Some characteristics of (METALS/NONMETALS) include…
Metalloids are elements that…
As you move (DOWN/ACROSS) the Periodic Table the number of (shells/valence electrons) increases…
As you move across the Periodic Table, elements become (MORE/LESS) metallic.
As you move down the Periodic Table, elements become (MORE/LESS) reactive.