Topic 5: The Periodic Table
Key Concept
Definitions and facts
1. Periodic Law
Properties of the elements Elements are
are periodic function of
arranged in order of
their atomic number
increasing atomic #
2. Period
The horizontal
arrangements of the
elements
. elements in the same
period have the same
# of electrons shells
. Period number indicates
# of electron shells
3. Group (families)
Properties of elements
The vertical arrangement
of the element
. Elements in the same
Group have same # of
valance electrons,
therefore, same
chemical reactivity
Examples
Mg and Si (both in
Period 3) have the
same number of
electron shells (3)
O and S (both in
Group 16) have
similar chemical
reactivity b/c they
each have 6 valance
electrons.
4. Malleable
able to be hammered into Gold is malleable
a thin sheet
5. Ductile
able to be drawn into wire Copper is ductile
6. Brittle
shatters easily when struck Sulfur is brittle
7. Luster
shininess
Silver has luster
8. Conductivity
able to conduct heat and
electrical current
Copper has high
conductivity
9. Electronegativity
ability to attract (or gain) e-
Values for these
10. Ionization Energy energy to remove (lose)
the most loosely bound e12. Density
mass per unit volume
13. Atomic Radius
size of a neutral atom
14. Ionic Radius
size of an ion
four properties
can be found on
Reference Table S
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Topic 5: The Periodic Table
15. Types of elements and locations
Black: Solids
Blue: Liquids
16. Properties of the elements
2
Orange: Gases
17. Groups on the Periodic Table
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Topic 5: The Periodic Table
18. Group names and Properties: Summary Table
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Topic 5: The Periodic Table
Selected Properties
Selected Elements
Examples
19. Very reactive elements.
Obtain from fused salts.
Not found in nature in
free (elemental) state.
Group 1 (alkali metals )
Group 2 (alkaline earth)
Fluorine
K
Ca
F
20. The most active metal
(lowest ionization energy)
Francium (Fr)
21. The most active nonmetal
(highest electronegativity)
Fluorine (F)
23. Radioactive elements (no
stable isotope)
All Element with atomic
number 83 and above
Bi (# 83)
Ra (# 88)
24. Monatomic (one-atom)
elements
All Group 18 noble gases
Ne Ar He
25. Diatomic (two-atoms)
elements
H2 N2 O2 F2 Cl2 Br2 I2
26. Element with a double bond
oxygen O2
O=O
27. Element with a triple bond
nitrogen N2
N=N
28. Elements that form colorful
compounds
Transition elements
(Group 3-12)
Cu Fe Mn
Na
Mg
CuSO4 is
bluish color
Oxygen allotropes
Air (O2)
Ozone (O3)
29. Allotropes: Same element in solid state with
. Different molecular forms
. Different physical and chemical
properties
Topic 2: The
Carbon allotropes
Diamond
Graphite
Phosphorus allotropes
Black
Red
Periodic Table
White
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Topic 5: The Periodic Table
Key Property
Period Trend
(Left to Right)
Group Trend
(Top to Bottom)
30. Atomic Radius Decreases (due to an
increase in + nuclear
charge)
Increases (due to an
increase in number of
electron shells
ex. Li (+3 nuclear charge)
is bigger than Be (+4
nuclear charge)
ex. O (2 electron shells) is
smaller than S (3 electron
shells)
31. Electronegativity Increases (due to
decreasing atomic size)
Decreases (due to
increasing atomic size)
ex. Li has a smaller
electronegativity value
(1.0) than Be (1.6)
32. Ionization
energy
Increases (due to
decreasing atomic size)
ex. Li has a smaller
ionization energy
value (520) than Be (900)
ex. O has a higher
electronegativity value
(3.4) than S (2.6)
Decreases (due to
increasing atomic size)
ex. O has a higher
ionization energy value
(1314) than S (1000)
34. Metallic
Properties
Decreases
Increases
35. Nonmetallic
Properties
Increases
Decreases
36. Summary of Trends
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