1. Periodic Table

2. History Antoine Lavoisier – Father of Modern Chemistry
1829 German J. W. Dobereiner Grouped elements into triads
Three elements with similar properties
Properties followed a pattern
The same element was in the middle of all trends
Not all elements had triads

3. Law of Octaves 1862 John Newlands developed Law of Octaves
The elements showed a repetition in their chemical properties after 8 elements
Used Atomic Weights but not actual values
Important because showed the first pattern of repeating properties

4. Julius Lothar Meyer
Meyer first table published 1864 containing 28 elements
Arranged in order of Atomic Weight and made a clear horizontal relationship between Atomic Weight and Atomic Volume
Allowed physical properties to outweigh chemical properties
Anticipated Mendeleev by years

5. Meyer Left gaps to denote unknown elements
Not willing to make predicitions
More focused on Physical properties not chemical properties
Bitter battle with Mendeleev
Lost to Mendeleev because of Mendeleev’s forceful ways

6. Dmitri Mendeleev
Mendeleev was known as the “Father of the Periodic Table”
DOB:
Created the first table on
Table had 70 elements
Used properties to set up table

7. History
Russian scientist Dmitri Mendeleev taught chemistry in terms of properties
Mid 1800 – atomic masses of elements were known
Wrote down the elements in order of increasing mass
Found a pattern of repeating properties
Not first to develop system but his version had the strongest impact

8. Mendeleev’s Table
Grouped elements in columns by similar properties in order of increasing atomic mass
Found some inconsistencies - felt that the properties were more important than the mass, so switched order.
Found some gaps
Must be undiscovered elements
Predicted their properties before they were found

9. Mendeleev
Distinguished from competitors by a devotion to, and love for, the individuality of the elements that went hand in hand with an intimate knowledge of their chemical characteristics
Focused on both physical and chemical properties

10. Mendeleyev Cont. Chemical Properties Used: Atomic Weight vs. Valancey
He could only predict these properties
His work preceded chemical advances by 30 years
Produced his table 27 years before the first subatomic particle, the electron was discovered
Did not predict Noble Gases

11. Acceptance Mendeleev’s table received real acceptance in 1875
Discovery of Scandium, Germanium and Gallium showed Mendeleev’s predictions were correct.

12. “The elements were not being arranged to make a periodic table, but to fit the periodic table”

13. Meyer vs. Mendeleyev Julius Meyer (1830-1895)
Created a table that plotted:
Atomic Volume vs. Atomic Weight
Lost out to Mendeleev
Published before Meyer
Final Table:
Atomic Weight vs. Valency
Table had 8 columns but was missing Noble Gases
Discovered 30 years later

14. Modern Russian Table

16. Spiral Periodic Table

20. Changing of Table
Henry Moseley ( ) – changed table in 1913 by increasing atomic number
Biggest Impact
Glenn Seaborg – rare earth series from Actinium (89) up.
Current Table Used Today
Minor Changes – inner transitional Lu & Lr replaced La & Ac
Bohr first linked Quantum Theory

21. Today’s Table

22. More History First Classified Groups: Gases Non-Metals Metals Earths
First Elements Discovered:
Carbon
Sulfur
Copper
Gold & Silver
Iron
Tin
Antimony
Mercury
Lead
Oxygen (1772)
First Classified Groups:
Gases
Non-Metals
Metals
Earths

23. The Modern Periodic Table
Our current periodic table shows elements in order of increasing atomic number (#protons)
Elements in the same column have similar properties, and are called a group or family. Groups are designated in two ways:
A Roman numeral (I through VIII) and a letter (A or B)
An Arabic number (1-18)
A horizontal row of elements is a period. Elements in the same period have properties that tend to vary in a regular fashion. Periods are designated by an Arabic number (1-7).

24. Vertical Columns Known as Groups or a Family
Elements in same group have similar physical & chemical properties
Each group is identified by a group number and group letter

25. Groups and Periods
Figure 2.19

26. Similar Properties in Groups
Potassium metal reacts violently with water to producing a basic solution and flammable hydrogen gas.
All alkali metals react with water to produce hydrogen gas.
Figure 2.21

27. Classification of Elements
Groups
IA Alkali metals
IIA Alkaline Earth Metals
VIIA Halogens
VIIIA Noble Gases
Periods
Metals, Nonmetals, Metalloids
Main-group Elements, Transition Metals, and Inner-transition Metals.
Figure from p. 73

28. Main-Group Elements and Transition Metals
Main-group elements (also called representative elements) contain any element in the eight groups designated with the letter A. (In the Arabic numbering, groups 1, 2, and 13-18)
Transition metals contain any element in the 10 groups designated with the letter B. (In the Arabic numbering, groups 3-12)
Inner-transition metals contain the lanthanides and actinides listed separately at the bottom of the table.

29. Common Group Names
Some groups have descriptive names that are commonly used instead of their group numbers.
Alkali metals
Group 1 (IA) metals (hydrogen is a nonmetal)
are considered reactive because the react readily with other elements and compounds
Alkaline earth metals
Group 2 (IIA) metals
are more reactive than the transition metals but less reactive than alkali metals

30. Common Group Names
Some groups have descriptive names that are commonly used instead of their group numbers.
Halogens
Group 17 (VIIA) nonmetals
exist naturally as diatomic molecules
Noble gases
Group 18 (VIIIA) nonmetals
are also called inert gases
are so named because they do not chemically react with other elements (with the exception of krypton and xenon)

31. The elements in the A groups are called the representative elements

32. Transition metals
The Group B elements

33. IA IIA IIIB IVB VB VIB VIIB VIIIB IIIA IVA VA VIA VIIA VIIIA IB IIB 1
Other Systems IA
IIA
IIIB
IVB VB
VIB
VIIB
VIIIB
IIIA
IVA VA
VIA
VIIA
VIIIA IB
IIB 1 2 13 14 15 16 17 18 3 4 5 6 7 8 9 10 11 12 1A 2A 3A 4A 5A 6A 7A 8A 3B 4B 5B 6B 7B 8B 1B 2B

34. Horizontal rows are called periods
There are 7 periods

35. Group 1A are the alkali metals
Group 2A are the alkaline earth metals

36. Group 7A is called the Halogens
Group 8 are the noble gases

37. The group B are called the transition elements
These are called the inner transition elements and they belong here

39. Metals, Nonmetals, and Metalloids
The periodic table has many classifications. Groups and periods are one classification. Another classification denotes metals, nonmetals, and metalloids.
A stair-step line starting at boron (B) separates metals (to the left of the line) from nonmetals (to the right of the line).
The metalloids exist along the line.
Metalloids are elements that have physical properties resembling a metal, but the chemical reactivity of a nonmetal.

40. Metals

41. Metals & Their Properties
Metals are good conductors of heat and electricity
Metals are malleable
Metals have high luster

42. Example of Metals
Copper is a relatively soft metal and a very good electrical conductor
Mercury is the only metal that exists as a liquid at room temperature

43. Non-metals

44. Nonmetals & Their Properties
Carbon, the graphite in a pencil is an example of a nonmetallic elements
Nonmetals are poor conductors of electricity
Can be brittle
Non-lustrous
Many are gases at room temperature

45. Example of Nonmetals Sulfur was once known as Brimstone
Microspheres of phosphorus, a reactive nonmetal

46. Metalloids or Semimetals
Properties of both
Semiconductors

47. Example of a Metalloid Silicon is a metalloid
Silicon is brittle like a nonmetal
Silicon has metallic luster
Silicon is a semiconductor of electricity

48. Metals, Nonmetals, and Metalloids
Figure 2.20

49. Chapter 2: Atoms, Molecules, and Ions
Modern Periodic Table
Elements are divided into two main classes
EOS
Chapter 2: Atoms, Molecules, and Ions

50. Chapter 2: Atoms, Molecules, and Ions
Modern Periodic Table
Except for hydrogen, those elements to the left of the line are metals
EOS
Chapter 2: Atoms, Molecules, and Ions

51. Chapter 2: Atoms, Molecules, and Ions
Modern Periodic Table
Elements to the right of the line are nonmetals
EOS
Chapter 2: Atoms, Molecules, and Ions

52. Chapter 2: Atoms, Molecules, and Ions
Modern Periodic Table
Elements around the line are referred to as metalloids
EOS
Chapter 2: Atoms, Molecules, and Ions