1. Chapter 5: The Periodic Table
5.1 Organizing the elements
5.2 The Modern Periodic Table
5.3 Representative groups

2. Organization of the Elements
Section 5.1
Organization of the Elements

3. Search for Order 1750 only 17 elements known
1789 Antoine Lavoisier grouped known elements (4 groups)
Metals
Non-metals
Gases
Earths
Next 80 yrs scientists looked for better way to classify known elements

4. Mendeleev’s Periodic Table
1869….Dmitri Mendeleev (Russian teacher and chemist) organized known elements while playing solitaire
Made deck of cards with elements
Listed name, mass and properties
Paid attention to how elements reacted in chemical reactions

5. Mendeleev’s Periodic Table
Strategy for organization: What did he look at?
chemical properties
physical properties
atomic mass
density
color
melting point
Valence electrons (sec 5.3)

6. Mendeleev’s Proposal
Elements arranged in rows based on increasing mass.
Elements with similar properties are in same column.
Chart was a Periodic Table - arrangement of elements in columns based on a set of properties that repeat.

7. Mendeleev’s Prediction
Table incomplete– elements not yet discovered
Left spaces in table for undiscovered elements
Good models allow for predictions to be made based on model
Used properties of nearby elements to predict properties of unknown elements

8. He called this element eka-Aluminum.
Later it was renamed Gallium after its discovery in 1875

9. Evidence Supporting Mendeleev’s Table
Close match between Mendeleev’s predictions and the actual properties of new elements showed how useful table was.
Ex. Discovery of: Aluminum, Gallium, Scandium, and Germanium

10. The Modern Periodic Table
YOU NEED 3 DIFFERENT COLORED PENCILS
Section 5.2
The Modern Periodic Table
The Elements by Tom Lehrer

11. The Modern Periodic Table
“Periodic” - Repeating patterns
Listed in order of increasing number of protons (atomic #)
Properties of elements repeat
Periodic Law- when elements arranged by increasing number of protons, properties repeat in pattern

12. Columns in the Periodic Table
-vertical (up & down)
-called groups or families
-#ed 1-18 or 1A through 8A
-elements in same family have similar properties

13. Rows in the Periodic Table
-horizontal (left – right)
-called a period
-properties change greatly across period
-first element in period is very active metal
-last element in most periods is noble gas
-7 periods (number them on your periodic table)

15. 6 C Carbon 12.01 For example: Carbon has atomic # 6
Element Key
Important information about an element is given in each square of the periodic table:
its atomic number
chemical symbol
element name
average atomic mass
6 C Carbon 12.01
For example:
Carbon has atomic # 6
(or has 6 protons), an average atomic mass of and a symbol of C

16. Two isotopes of copper 72% copper-63 28% copper-65
Atomic Mass
Two isotopes of copper
72% copper-63
28% copper-65
Makes the average amu

17. Determining Average Atomic Mass

18. Metals Most solids (Hg is liquid) Luster – shiny.
Ductile – drawn into thin wires.
Malleable – hammered into sheets.
Conductors of heat and electricity.
Include transition metals – “bridge” between elements on left & right of table

19. Non-Metals Properties are generally opposite of metals
Poor conductors of heat and electricity
Low boiling points
Many are gases at room temperature
Solid, non-metals are brittle (break easily)
Chemical properties vary

20. Metalloids stair-step pattern
Have properties similar to metals and non-metals
Ability to conduct heat and electricity varies with temp
Better than non-metals but not metals

21. Variation Across a Period: Left to Right
Physical and Chemical properties
Atomic size decreases
Metallic properties decrease
Ability to lose an electron decreases
Ability to gain electrons increases

23. Representative Groups
Section 5.3
Representative Groups
Hip Hop Classroom
The Elements

24. What are Valence electrons?
outermost e-’s
Responsible for chem props
Elements in same group…
same # of VE
ALL atoms want full outer
energy level (usually 8 VE)
To get full outer energy level, some elements:
lose e- (metals)
gain e- (non-metals)
share electrons (some non-metals & metalloids)

25. Introducing the ten major groups (families) on the modern Periodic Table:

26. Alkali Metals - 1 valence electron (VE)
potassium
- 1 valence electron (VE)
- soft, silver-white, shiny metals
never found pure
most reactive metals
Reactivity increases down group
reactivity increases

27. Label the Alkali Metals to your PT

28. Alkaline Earth Metals - 2 VE - not as reactive as alkali metals
magnesium
- 2 VE
- not as reactive as alkali metals
often mixed with Al
forms strong/light weight alloys

29. Alkaline Earth Metals Magnesium Calcium
Used to make steel (light metal w/o losing strength)
photosynthesis (chlorophyll)
Calcium
bones & teeth
Chalk, limestone, pearls, plaster

30. Label the Alkaline Earth Metals to your PT

31. Boron Family -3 VE Boron Hard/brittle never found pure in nature
in borax...used to make detergents & cosmetics

32. Boron Family 13 Al Aluminum 26.98 Aluminum
most abundant metal in earth’s crust
important metal for industry
light, strong, slow to corrode
13 Al Aluminum 26.98

33. Label the Boron Family on your PT

34. Carbon Family 4 VE Can gain 4 e-, lose 4 e-, or share e-
silicon
4 VE
Can gain 4 e-, lose 4 e-, or share e-
Most compounds in body contain C
Si 2nd most abundant element in Earth’s crust
Si used to tip saw blades

35. Label the Carbon Family on your PT

36. Nitrogen Family 5 VE Tend to gain 3 e- N and P used in fertilizers
Arsenic
5 VE
Tend to gain 3 e-
N and P used in fertilizers
P on tips of matches

37. Label the Nitrogen Family on your PT

38. Oxygen Family 6 VE Tend to gain 2 e- O very abundant element
sulfur
Oxygen Family
6 VE
Tend to gain 2 e-
O very abundant element
S used in fertilizers
O needed for digestion

39. Label the Oxygen Family on your PT

40. Halogen Family (“salt-former”)
-7 VE
-most active nonmetals
-never found pure in nature
-react with alkali metals easily (forms salts)
-F most active halogen

41. F compounds in toothpaste Cl kills bacteria
Halogens cont…
bromine
F compounds in toothpaste
Cl kills bacteria
I keeps thyroid gland working properly

42. Label the Halogen Group on your Periodic Table

43. The Noble Gases (Inert Gases)
Neon
- non-reactive
outermost e- shell is full (8 VE)
In “neon” lights
-in earth’s atmosphere (less than 1%)

44. Label the Noble Gases on your Periodic Table

45. Transition Metals ductile, malleable, conductors
mercury
Almost all solids at room temp (Hg exception)
ductile, malleable, conductors
VE varies
Less Reactive than Groups 1 & 2
Fe, Co, and Ni produce magnetic field

46. Label the Transition Metals on your periodic table

47. Rare Earth Elements Lanthanide series (period 6)
uranium
Lanthanide series (period 6)
Actinide Series (period 7)
Some radioactive
Separated from table to make easy to read/print
silver, silvery-white, or gray metals.
Conduct electricity

48. Label the Lanthanide Series on your PT

49. Label the Actinide Series on your PT

50. You may watch more videos about the elements at:
or sing along at:
elemental funkiness - Mark Rosengarten
hip hop classroom