1. Take out your notes and get ready to ROCK!
Take out your notes and get ready to ROCK!

2. Periodic Trends REvisited

3. Mendeleev’s Periodic Table
Dmitri Mendeleev

4. Periodic Law (Periodicity)
Properties repeat at regular intervals when elements are arranged according to increasing atomic number
Group/family = column; Period = row

5. Period
The Periodic Table
Group or Family
Group or family
Period

6. The Properties of a Group: the Alkali Metals
Easily lose valence electron
(Reducing agents)
React violently with water
Large hydration energy
React with halogens to form salts

7. Properties of Metals
Metals are good conductors of heat and electricity
Metals are malleable
Metals are ductile
Metals have high tensile strength
Metals have luster

8. Properties of Nonmetals
Carbon, the graphite in “pencil lead” is a great example of a nonmetallic element.
Nonmetals are poor conductors of heat and electricity
Nonmetals tend to be brittle
Many nonmetals are gases at room temperature

9. Properties of Metalloids
Metalloids straddle the border between metals and nonmetals on the periodic table
They have properties of both metals and nonmetals.
Metalloids are more brittle than metals, less brittle than most nonmetallic solids
Metalloids are semiconductors of electricity
Some metalloids possess metallic luster

10. Inner Transition/Rare Earth Metals
Transition Metals
Alkaline Earth Metals
Noble Gases
Inner Transition/Rare Earth Metals
Halogens
Alkali Metals

11. Metal/Metalloid/Nonmetal
Metals
Metalloids
Nonmetals

12. Representative Elements (1,2,13 – 18)
1 B  10 B

13. INC INC Atomic Number = # of protons
Atomic Mass = # of protons & neutrons
INC
INC

14. Shielding= e- between nucleus and outer e-
Nuclear Pull= electrostatic attraction of the + nucleus for the outer e-
Shielding= e- between nucleus and outer e-
INC
Constant

15. e- are added to successively higher energy levels.
Atomic Radius = the distance between the nucleus and the outermost electrons.
e- are added to successively higher energy levels.
We remain in the same principle energy level. Each element has one p+ and one e- more than the preceding element. The nuclear pull increases pulling each new e- closer to the nucleus.
INC
INC
INC

16. Increasing atomic radiiH
0.030 Na
0.157 K
0.203 In
0.150 Sr
0.191 Rb
0.216 Sn
0.140 Sb Te
0.137 I
0.133 Ca
0.174 Ga
0.125 Ge
0.122 As
0.121 Se
0.117 Br
0.114 Mg
0.136 Al Si P
0.110 S
0.104 Cl
0.099 Li
0.123 Be
0.089 B
0.080 C
0.077 N
0.070 O
0.066 F
0.064
The atomic radii of these representative elements are given in nanometers (nm).
Increasing atomic radii

17. Period Trend: Atomic Radius

18. Ionic Radius (Size) Size or radius of an ion
INC
Cations
Anions
The overall trend is the same as Atomic size – for the same reasons, however:
Cations have lost e- so they are smaller
Anions have gained e- so they are larger

19. The ionic radii shown here are given in nanometers.
0.140 F-
0.136
Be2+
0.031
Li+
0.060
Cs+
0.169
Tl3+
0.095 K+
0.133
Ca2+
0.099
Na+
N3-
0.171
Cl-
0.181
S2-
0.184
P3-
0.212
As3-
0.222
Ba2+
0.135
Rb+
0.148
Sr2+
0.113
In3+
0.081
Sn4+
0.071 I-
0.216
Te2-
0.221
Sb3-
0.245
Ga3+
0.062
Ge4+
0.053
Se2-
0.198
Br-
0.195
Pb4+
0.084
Al3+
0.050
Mg2+
0.065
Si4+
0.041
B3+
0.020
C4+
0.015
The ionic radii shown here are given in nanometers.

20. New TRENDS
e- Configuration = arrangement of e- around nucleus s d p f

21. Electronegativity = tendency of an atom to attract (pull) bonded e- to itself (noble gasses omitted)

22. Periodic Table of Electronegativities

23. Electronegativity

24. Valence Electrons = outermost e- (e- in the highest principle energy level) 2 8

25. Ionic Charge (oxidation number) = charge of atom once it has lost or gained electrons+1 +2 +3 ±4 -3 -2 -1

26. ↑ harder to remove e- as atom gets smaller.
Ionization Energy = how much energy it takes to remove an e- from a gaseous atom. (1st ionization energy trend)
↑ harder to remove e- as atom gets smaller.
INC

27. Table of 1st Ionization Energies

28. 1st Ionization Energy = energy to remove 1st e-
2nd “ “ = “ “ “ nd e-
Atoms want to have the e- configuration of a Noble gas.
Atoms are more stable when they have full or ½ full sublevels.
Atoms will easily lose or gain e- until they have a noble gas configuration. After that it will take a lot of energy to remove any e-.

29. Ionization Energy

30. Summation of Periodic Trends