1. Periodic Table 1869 Dmitri Mendeleev in Russia Lothar Meyer of Germany
Published nearly identical schemes

2. Henry Moseley
1913
Developed the concept of atomic numbers

3. Groups Vertical Columns Families Elements have similar properties
Same number of valence electrons (the number of electrons in outer most shell)

4. Periods Horizontal rows
Period number corresponds to number of energy levels

5. GROUP IA GROUP IIA GROUP VIIA GROUP VIII (0) 2 Period
Transition Metals
GROUP IIIA
GROUP IVA
GROUP VA
GROUP VIA
   GROUP VIIA
   GROUP VIII (0) 1
2 He -
   2
3 Li 1.0
4 Be 1.5
5 B 2.0
6 C 2.5
7 N 3.0
8 O 3.5
9 F 4.0
10 Ne - 3
11 Na 0.9
12 Mg 1.2
13 Al 1.5
14 Si 1.8
15 P 2.1
16 S 2.5
17 Cl 3.0
18 Ar - 4
19 K 0.8
20 Ca 1.0
21 Sc 1.3
22 Ti 1.5
23 V 1.6
24 Cr 1.6
25 Mn 1.5
26 Fe 1.8
27 Co 1.9
28 Ni 1.9
29 Cu 1.9
30 Zn 1.6
31 Ga 1.6
32 Ge 1.8
33 As 2.0
34 Se 2.4
35 Br 2.8
36 Kr - 5
37 Rb 0.8
38 Sr 1.0
39 Y 1.2
40 Zr 1.4
41 Nb 1.6
42 Mo 1.8
43 Tc 1.9
44 Ru 2.2
45 Rh 2.2
46 Pd 2.2
47 Ag 1.9
48 Cd 1.7
49 In 1.7
50 Sn 1.8
51 Sb 1.9
52 Te 2.1
53 I 2.5
54 Xe - 6
55 Cs 0.7
56 Ba 0.9
57 La 1.1
72 Hf 1.3
73 Ta 1.5
74 W 1.7
75 Re 1.9
76 Os 2.2
77 Ir 2.2
78 Pt 2.2
79 Au 2.4
80 Hg 1.9
81 Tl 1.8
82 Pb 1.9
83 Bi 1.9
84 Po 2.0
85 At 2.2
86 Rn - 7
87 Fr 0.7
88 Ra 0.9
89 Ac 1.1
104 Rf -
105 Ha -

6. Periodic Table Most of the elements are metals
Gases – H,N,O,F,Cl and Group 18
Liquids – Hg and Br

7. Metals Left of zig zag line
Low ionization energy and electronegativity
Lose electrons to form positive ions
Metallic luster when polished
Good conductor of heat and electricity
Malleable (made into sheets)
Ductile (made into wire)
Most are solid at room Temperature (Hg is a liquid)

8. Lower Left of Table Most Metallic Character Most reactive metal
YouTube - Brainiac Alkali Metals

9. Nonmetals Right of zig zag line (except group 18 – Noble gases)
Gain electrons to form form negative ions
High ionization energy (attraction for electrons) and high electronegativity
Lack luster and form brittle solids
Poor conductors of heat and electricity
Exist as gases (mostly) solids (molecular or network) bromine is a volatile liquid at room temperature.

10. Metalloids Touch zig zag Known as semi-metals
At the border of metals and nonmetals
Properties are similar to metals and nonmetals
Boron, silicon, germanium, arsenic, antimony and tellurium

11. Metalloids

12. Group 1 Elements Alkali Metals One valence electron
React with acids to product hydrogen gas
Form strong bases

13. Group 2 Metals
Alkali earth metals
2 valence electrons
Form weak bases

14. Metals Reactivity increases as we go down a group
Reactivity decreases as we go across a period (left to right)
Ex. Sodium is more reactive than Magnesium (period 3)
Why? Sodium wants to give the one electron away faster.
Group 1 – larger atomic size
Group 2 – greater nuclear charge

15. Group 17 Halogens 7 valence electrons Diatomic molecules
High electronegativity
Very reactive, occurs in nature only as compounds
All three phases of matter exist.

16. Phases Fluorine and chlorine are gases Br is a liquid
Iodine and astatine are solids

17. Group 18
Noble Gases
Inert Gases-old name, they were thought to be unreactive.
Chemically unreactive
Completely filled valence shells
Monoatomic

18. Groups 3-11 Transition elements Positive oxidation states
Formed colored compounds
d sublevels – lose electrons from an inner energy level
Forms ions of more than one stable charge
Ex. Fe2+ and Fe3+

19. Trends Bottom left most reactive metal
Top right (excluding group 18) most reactive nonmetal
Metals – reactivity increases as you go down a group
Nonmetals – reactivity increases as you go up a group

20. Ionization Energy Energy needed to remove an electron from an atom
The greater the attraction for electrons the more energy is needed to remove the electron
The smaller the ionization energy, the easier it is to remove an electron

21. Ionization Energy Li 520 B 801 O 1314 Ne 2081
Trend: Ionization Energy increases across a period.

22. Ionization Energy C 1086 Si 787 Ge 762 Pb 716
Trend: Ionization Energy decreases down a group.

23. Electronegativity
Is the attraction for electrons. The larger the electronegativity the more the atom attracts electrons.
3 Factors
Nuclear charge - # of protons, increase charge greater attraction
Principal energy level – The higher the principal energy level of the outermost electrons, the greater the distance from the nucleus, the weaker is the pull
Electron Cloud Effect – shields the outermost electrons from the nucleus. The inner electrons repel outermost electron

24. Electronegativity Li 1.0 B 2.0 O 3.4 Ne -----
Why doesn’t Ne have an Electronegativity?
It is not reactive. Does not react with any element.
Trend Electronegativity increases across a period.

25. Electronegativity
C 2.6
Si 1.9
Ge 2.0
Pb 1.8
F 4
Cl 3.2
Br 3.0
I 2.7

26. Electronegativity decreases down a group.
Trend:
Electronegativity decreases down a group.

27. Atomic Radius
Is half the distance between adjacent nuclei (the distance from the nucleus to the outer most valence electrons).
Size of the atom
Related to the attraction of the nucleus for its electrons
Decreases as the atomic number increase as a result of the force of attraction between the positive nucleus and the negative electrons.

28. Atomic Radius
Li 130
B 84
O 64
Ne 62
Trend: Atomic Radius decreases across a period.

29. Atomic Radius
C 75
Si 114
Ge 120
Pb 145
Trend: Atomic Radius increases down a group.

30. Ionic Radius Metals lose electrons, ionic radius becomes smaller
Nonmetals gain electrons, the ionic radius becomes larger

31. What do all of these have in common?

32. They are all Carbon.

33. What do all of these have in common?
Graphite
Carbon Fiber Clothes
Artist’s Charcoal
Carbon Fiber Custom Wheel
Charcoal
Diamond

34. Aren’t we all the same deep down?
Allotropes
Aren’t we all the same deep down?

35. What is an allotrope?
A structurally differentiated form of an element that exhibits allotropy.

36. What is allotropy?
A property of certain elements, as carbon, sulfur, and phosphorus, of existing in two or more distinct forms.

37. A.K.A.
When an element exists in pure forms that differ in the way the atoms are arranged.

38. Buckminsterfullerene

40. Sulfur Phosphorous Oxygen P4 and P2 Other Allotropes S4, S5, S8
O2 and O3