1. We will learn to use the periodic table as tool
Like a calculator in math class

3. Properties of Metals
Good conductors of heat & electricity—called conductors
Shiny
Ductile--can be stretched into thin wires

4. Properties of Metals Malleable--can be pounded into thin sheets
Corrodes--reacts with oxygen in the air to form new compound

5. Properties of Non-Metals
Poor conductors of heat & electricity—called insulators
Not ductile or malleable
sulfur

6. Properties of non-metals
Many non-metals are gases
Solid non-metals are brittle
--means break easily
Dull
CARBON

7. Another suffix: -oid Suffix -oid means “like” or “resembling”
Examples:
humanoid
asteroid

8. Metalloids
Elements that sometimes behave like metals and sometimes not
7 of these

9. Properties of Metalloids
germanium
Properties of Metalloids
Can have properties both metals & non-metals—depending on use
semi-conductors
Separate metals and nonmetals
germanium

10. Location of element on periodic table will “tell” us a lot about element

11. Metalloids

12. Non-Metal

13. Metals

14. Why are elements #57-102 placed at the bottom of the periodic table?

15. Reason for separation- convenience
If table were put together the periodic table would not fit on a single sheet of paper.

17. Periodic Table in sections
Red lines

18. Periodic Table
Arranged in several patterns
We will learn many

19. Rows
Horizontal arrangements of elements 7
Called periods

20. Periods 1 2 3 4 5 6 7 6 7

21. Columns
Vertical arrangements of elements 18
Called groups or families

22. Groups or Families 1 18 2 13 14 15 16 17 3 4 5 6 7 8 9 10 11 12

23. Family Names a.k.a. Group Names

24. Family Names Group 1—Alkali Metals Group 2—Alkali Earth Metals
Group 3-12—Transition metals
Group 13—Boron Family
Group 14—Carbon Family
Group 15—Nitrogen Family
Group 16—Oxygen Family
Group 17—Halogen Family
Group 18—Inert Gases or Noble Gases

25. Family Characteristics
Group 1—Alkali Metals (pH greater than 7 which means they are bases) Most reactive group
Group 2—Alkali Earth Metals (pH greater than 7 which means they are bases)
Group 3-12—transition metals (their electron arrangement can change)
Group 13—Boron family
Group 14—Carbon family

26. Family Names Group 15—Nitrogen family Group 16—Oxygen family
Group 17—Halogens (produce salt)
Group 18—Noble gases or inert gases (will NOT react with anything)

27. Names of the elements at bottom (remember not GROUP)
Elements are Lanthanides
Elements are Actinides
Elements make up the Rare Earth Metals

28. Cr 24 chromium Reading each block on the periodic table 51.996
Chemical name or
Element name
Average atomic mass
chromium
51.996 Cr
Chemical symbol or
Element symbol
Atomic number 24

29. FYI
#92, U, is last natural element
Every element after #92, U, is synthetic

30. Chemical symbols 1, 2, or 3 letters
Used instead of writing chemical name
Universal
“Language of Chemistry”
Style of how letters are written matters
Size of how letters are written matters
Rules for writing chemical symbols:
1st letter MUST be written uppercase
Any following letter MUST be written lowercase
No cursive

31. What does symbol mean? Use symbols instead of words
H means one atom of hydrogen
Rh “ “ “ “ rhodium
Cu “ “ “ “ copper
Ti “ “ “ “ titanium

32. These have same answer.
Write something that means “one atom of lithium.” Li
What is the symbol for lithium?

33. Question:
The symbol for thallium is Tl. This is an uppercase t and a lowercase L. How do we know that is an L and not an i?

34. Answer #1:
Second letter of every symbol is ALWAYS lowercase. If the second letter were an uppercase I that would be violating symbol writing rule.
Besides Ti is symbol for titanium. Symbols are NEVER duplicated.

35. Atomic numbers Whole numbers—always!!! Never duplicated
Periodic table is arranged by increasing atomic numbers

36. Average Atomic mass
Measure of how much matter there is an atom or subatomic particles (e-, p+, n0)
So tiny—created new unit--atomic mass measured in atomic mass unit (amu)
Atomic mass on periodic table are averages*

37. Usually decimal number Can be written in parentheses
Average atomic mass
Usually decimal number
Can be written in parentheses
--means atomic mass is estimated
Can be duplicated

38. Why some atomic masses are estimated?
Some elements are unstable
Decompose quickly
Measuring mass is difficult
Some elements are synthetic
--means man-made

39. How can I tell the atomic mass of an element from its atomic number?
Question
How can I tell the atomic mass of an element from its atomic number?

40. Answer:
--Atomic mass is usually a decimal number or will be written in parentheses that means the other whole number in the box must be the atomic number

41. Now… What we know: What periodic table is
What words on periodic table are
What numbers on periodic table are
What symbols on periodic table are
What classification each element is on periodic table
What some of the properties are for each element
What are the family names
Now…

42. Elements within a section have similar atomic structure

43. Atoms Abbreviations electron e- proton p+ neutron n0
Smallest particle of element that has properties of that element
Made-up of:
electrons
protons
neutrons
Abbreviations
electron e-
proton p+
neutron n0

44. Charges of e-, p+, and n0? Electrons= negative e- Protons=positive p+
Neutrons=neutral n0
(neutral means no charge)

45. Where are e-, p+ & n0 located?
Electrons—outer limits of atom in area called electron cloud
Protons & neutrons—innermost area of atom called nucleus
Electron cloud has a negative charge.
Nucleus has a positive charge.

46. Charge of every atom Neutral Why??? Example: silver 47- (electrons)
47+ (protons)
_________
neutral charge

47. Atoms Review Electrons --charge of each 1- --located: electron cloud
Protons
--charge of each 1+
--located: nucleus
Neutrons
--no charge/neutral

48. FYI: Mass of subatomic particles
Mass of 1 proton = 1 amu
Mass of 1 neutron = 1 amu
Mass of 1 electron = 1/2000 of an amu
--Takes 2000 electrons to = 1 amu
--Extremely, extremely, extremely, extremely, extremely, small

49. Atomic structure
How many protons?
--atomic number
How many electrons?

50. Using atomic mass
Round to a whole number; known as an element’s mass number
Number of protons and neutrons in nucleus
For example: atomic mass mass #
bromine

51. Atomic mass—mass number
Gold has atomic mass of amu which rounds to 197
197 is number of protons and neutrons in nucleus
Gold has 79 protons so remaining particles in nucleus are neutrons
197 (mass number) – 79 (p+) = 118 (n⁰)

52. Atomic structure How many protons? --atomic number How many electrons?
How many neutrons?
--mass number minus atomic number
--mass number minus protons

53. Electrons, electrons, electrons

54. Electrons
Electrons have negative charge and are found in electron cloud in energy levels
There are 7 energy levels
Valence electrons are the electrons that are the farthest from the nucleus—found in outermost energy level---maximum number is 8
Periodic table will give you this information

55. Valence Electrons
An element that has 8 valence electrons is “happy”—will not react
EXCEPTION: Helium is “happy” with 2 because it has only one energy level and the maximum number of electrons in that energy level is two

56. Electrons 1 18 1 2 13 14 15 16 17 2 3 3 4 5 6 7 8 9 10 11 12 4 5 6 7 6 7

57. Atomic Structure “Cheats”
Mass number- average atomic mass rounded to a whole number.
# p+atomic number
#n⁰ mass number minus p+
#e- same as p+
# Ve-  ones place of group number with the exception of groups 3-12 which can NOT be predicted
Energy level  period #

58. Periodic Table in orbits1 * 1 D 2 2 3 3 4 4 5 5 6 6 7 7 6 F 6 7 7

59. Electron Configuration
1S² # of e- in that orbit
Energy Level Orbit

60. Electron Configuration of Ga:
1S²2S²2P⁶3S²3P⁶4S²3D¹º4P¹

61. Constructing atomic models
Entire model elements 1 – 20
Model of nucleus for every other element

62. Step 1—atomic model
Draw circle (representing nucleus) Al

63. Step 2—atomic model
Write p and n in nucleus Al p n n p

64. Step 3—Insert correct values14 n p 13
This model shows 13 protons and 14 neutrons.

65. Step 4—add energy levels*
Circles should be
concentric. Al 14 n 13 p
Remember:
This circle represents
the nucleus; it is NOT
an energy level.
*Can be determined by using periodic table.

66. Step 5 – add electrons (proper number & location)
Each energy level holds a specific number of e-
P.T. shows you how many
Use P.T. as tool!!! Do not attempt to memorize a list of numbers!!!!!!!!!!!!!
(Examples given in class)
3rd – 7th energy levels more detail later

67. Step 6—add symbol Al
13 P
14 N