CHEMICAL PERIODICITY
• PERIODIC TABLE
• MENDELEEV
• PREDICTION OF PROPERTIES
• Chapters 8.4; 9.5; 14.1-14.10

14-1
Goals & Objectives
• See the following learning objectives on pages
322-323, 356, 563.
• Understand the Concepts:
• 8.9-12...
CHEMICAL PERIODICITY
• THE PERIODIC TABLE
– 1869 Russian chemist Dmitri Mendeleev published a periodic
table based on chem...
Mendeleev’s Periodic Table
Elements were grouped in order of
atomic mass; if the next known element
did not fit, Mendeleev...
Pictures of Mendeleev &
Meyer

14-5
Mendeleev’s Predictions

14-6
The Periodic Law
• The properties of the elements are
periodic functions of their atomic
number

• This change is based on...
Henry Moseley picture
• During the first World
War, Moseley was
killed while serving
as a pilot in the
British army at the...
Terminology
•
•
•
•
•
•
•
•

14-9

Group(family) of element - vertical column
Period(row) of elements - horizontal row
Gro...
Classification of the
Elements

14-10
Classification of the
Elements

Nonmetals

Transitions metals

14-11

Post trans.
Metals
This is a link to the Element
Song.
The Elements" (1959) is a song
by musical humorist Tom Lehrer,
which recites the names...
This is a link to the New
Element Song. The New
Periodic Table Song
(2013) is a song by ASCAP
Science, which recites the
n...
Chapter 14

Periodic Patterns in the Main-Group Elements

14-14
Hydrogen
• Hydrogen has a very simple structure:
– the nucleus has a single positive charge, and has 1 electron.

• Hydrog...
Hydrogen and Group 1
• Like the Group (1) elements, H has a half-filled valence
level.
• H is similar to the other Group 1...
Hydrogen and the Halogens
• Like the halogens or Group (17), hydrogen
– exists as a diatomic molecule and
– needs only 1 e...
Table 14.1

14-18

Trends in Atomic, Physical, and Chemical
Properties of the Period 2 Elements.
Table 14.1

14-19

Trends in Atomic, Physical, and Chemical
Properties of the Period 2 Elements.
Table 14.1

14-20

Trends in Atomic, Physical, and Chemical
Properties of the Period 2 Elements.
Table 14.1

14-21

Trends in Atomic, Physical, and Chemical
Properties of the Period 2 Elements.
Table 14.1

Trends in Atomic, Physical, and Chemical
Properties of the Period 2 Elements.

Trends in atomic radius, ioniza...
Group (1): The Alkali Metals

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The M...
Properties of the Alkali Metals
• Alkali metals are the largest elements in their respective
periods and their valence ele...
Periodic Properties
•
•
•
•
•

14-25

Electron configurations
Li [He]2s1
Na [Ne]3s1
K [Ar]4s1
Rb [Kr]5s1
Lithium floating in oil
floating on water. Alkali
metals have low densities.

14-26

Potassium reacting with
water. Alkali...
Demonstration of the Reactivity
of Alkali Metals
• The following YouTube video shows the
reactivity of the alkali metals.
...
Group (2): The Alkaline Earth Metals
• The oxides of Group (2) elements form basic solutions
and melt at extremely high te...
Group (2): The Alkaline Earth Metals

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright...
Group (13): The Boron Family

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The M...
Influence of Transition Elements on
Group (13)

The larger 13 elements have smaller atomic radii and
larger ionization ene...
Group (14): The Carbon Family

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The ...
Allotropes
Allotropes are different crystalline or molecular forms of
the same element.
One allotrope of a particular elem...
Figure 14.9

14-34

Phase diagram of carbon.
Figure 14.10 Crystalline buckminsterfullerene and a buckyball (A)
and nanotubes (B).
Copyright © The McGraw-Hill Companies...
Carbon in Organic Chemistry
The large number and wide variety of organic compounds
is due to the ability of C to bond to i...
Figure 14.12 Three of the several million known organic
compounds of carbon.

Lysine, one of 20 amino
acids that occur in ...
Inorganic Compounds of Carbon
Carbon bond with oxygen to form carbonates. Metal
carbonates such as CaCO3 are abundant in m...
Figure 14.13 Freon-12 (CCl2F2), a chlorofluorocarbon.

Chlorofluorocarbons (CFC’s or Freons) are chemically and thermally
...
Group (15) Elements
• Nitrogen is a diatomic gas (N2) with a very low boiling
point, due to its very weak intermolecular f...
Group (15): The Nitrogen Family

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © Th...
Figure 14.16

Two allotropes of phosphorous.

White phosphorous (P4)

Strained bonds in P4

Red phosphorous

14-42
Periodicvideos.com
• This is the periodic video for Phosphorus.
• Phosphorus Video

14-43
Patterns of Behavior in Group (15)
• N gains 3 electrons to form the anion N3-, but only in
compounds with active metals.
...
Oxides of Nitrogen
• Nitrogen forms six stable oxides. Hf for all six oxides is
positive because of the great strength of ...
Table 14.3

14-46

Structures and Properties of the Nitrogen Oxides
Group (16) Elements
• Oxygen, like nitrogen, occurs as a low-boiling diatomic
gas, O2.
• Sulfur, like phosphorus, occurs a...
Group (16): The Oxygen Family

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The ...
Allotropes in the Oxygen Family
Oxygen has two allotropes:
- O2, which is essential to life, and
- O3 or ozone, which is p...
Figure 14.20

The cyclo-S8 molecule.

top view

side view

At room temperature, the sulfur molecule is a crown-shaped ring...
Hydrides of the Oxygen Family
• Oxygen forms two hydrides:
– water (H2O) and hydrogen peroxide (H2O2).
– H2O2 contains oxy...
Halides of the Oxygen Family
Except for O, the Group 16 elements form a wide range of
halides.
Their structure and reactiv...
Highlights of Sulfur Chemistry
• Sulfur forms two important oxides:
– SO2 has S in its +4 oxidation state. It is a colorle...
Figure 14.21 The dehydration of sugar by sulfuric acid.

14-54
14-55
Group (17): The Halogens

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The McGra...
Reactivity of the Halogens
A halogen atom needs only one electron to fill its valence
shell. Halogens are therefore very r...
Group (18): The Noble Gases

Family Portrait

KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS
Copyright © The Mc...
Noble Gases
• Noble gases have a full valence shell.
• The noble gases are the smallest elements in their
respective perio...
Figure 14.26

14-60

Crystals of xenon tetrafluoride (Xe(F4).
Chapter 8

Electron Configuration and Chemical Periodicity

14-61
Periodic Properties
• Electronic configurations

s

p

d

f
14-62

f
Electron Configurations

14-63
Electron Configuration
• Give the symbol for the element
having the outermost electron
configuration 3s2

• Give the symbo...
14-65
Trends in Atomic Size
Atomic size increases as the principal quantum number n
increases.
As n increases, the probability t...
Figure 8.13
Atomic radii of the maingroup and transition
elements.

14-67
Figure 8.14

14-68

Periodicity of atomic radius.
Sample Problem 8.3
PROBLEM:

Ranking Elements by Atomic Size

Using only the periodic table (not Figure 8.15), rank each
s...
Sample Problem 8.3
SOLUTION:
(a) Sr > Ca > Mg
Ca, Mg, and Sr are in Group 2A. Size increases down the group.
(b) K > Ca > ...
Atomic Radii

size decreases
14-71
Atomic Radii
• Give the symbol for the larger of the
two atoms As or N
• Give the symbol for the atom having
the smaller r...
Ionization Energy (IE)
• The energy in kilojoules required for
the complete removal of one mole of
electrons from one mole...
Trends in Ionization Energy
Ionization energy (IE) is the energy required for the
complete removal of 1 mol of electrons f...
Figure 8.15

14-75

Periodicity of first ionization energy (IE1).
Figure 8.16

14-76

First ionization energies of the main-group elements.
Ionization Energy

IE increases
14-77
Ionization Energy

14-78
Ionization Energy

14-79
Sample Problem 8.4

Ranking Elements by First Ionization
Energy

PROBLEM: Using the periodic table only, rank the elements...
Sample Problem 8.4
SOLUTION:
(b) Te > Sb > Sn
Sb, Te, and Sn are in Period 5. IE1 increases across a period.
(c) Ca > K > ...
Ionization Energy
• Give the symbol for the element in
the same group as Sn having the
largest IE.

• Give the symbol for ...
Electron Affinity (EA)
• Electron Affinity is the energy change
in kilojoules accompanying the
addition of one mole of ele...
Trends in Electron Affinity
Electron Affinity (EA) is the energy change that occurs
when 1 mol of electrons is added to 1 ...
Figure 8.18

14-85

Electron affinities of the main-group elements
(in kJ/mol).
Behavior Patterns for IE and EA
Reactive nonmetals have high IEs and highly negative
EAs.
These elements attract electrons...
Electron Affinity

14-87
Electron Affinity

EA increases
14-88
Electron Affinity
• Give the symbol for the
representative metal in the same
period as As having the larger
electron affin...
Electronegativity (EN)
• Electronegativity is the relative ability of a
bonded atom to attract the shared electron pair
• ...
Pictures of Linus Pauling

14-91
Trends in Electronegativity
The most electronegative element is fluorine.

In general electronegativity decreases down a g...
Figure 9.22

14-93

Electronegativity and atomic size.
Electronegativity

EN increases
14-94
Electronegativity
• Give the symbol for the nonmetal in
the same period as Al having the
greatest EN.

• Give the symbol f...
Ionic Size vs. Atomic Size
Cations are smaller than their parent atoms while
anions are larger.
Ionic radius increases dow...
Ionic Radii
• Cations are always smaller than their
corresponding neutral atoms

14-97
Ionic Radii
• Anions are always larger than their
corresponding neutral atoms

14-98
Ionic Radii
• Give the symbol for the element with
the largest ionic radius between Cl
and Cl-1.

• Give the symbol for th...
Binary Compounds




A. Salt of metal cation with only one
charge and nonmetal anion
MgCl2





14-

metal + nonmetal...
Binary Compounds


Charges on metals









14-

Group 1
+1
Group 2
+2
Aluminum
+3
Zinc (Zn)
+2
Silver(Ag)
+1
Ca...
Binary Compounds







14-

lithium sulfide
barium chloride
aluminum bromide
AgCl
CdO
Al2O3
Binary Compounds


B. Salt of metal cation with more than
one possible charge and nonmetal anion
All metals not covered i...
Binary Compounds



IUPAC System
FeCl3, FeCl2



metal + stem of nonmetal+ide
charge on metal in Roman numerals




...
Binary Compounds







14-

NiO
CrCl3
SnCl4
Copper (II) bromide
Iron (III) oxide
Cobalt (III) nitride
Binary Compounds





14-

Older system
“ic “ suffix designates the higher of two
possible charges
“ous” suffix designa...
Binary Compounds









14-

Memorize these four ions for the older
system
Fe2+ - ferrous
Fe3+ - ferric
Cu+1 - cu...
Binary Compounds








14-

ferrous chloride
ferric sulfide
cuprous iodide
cupric bromide
mercuric chloride
mercu...
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  • Play the Elements Song – then play the new Elements song.
  • Then play the new Elements song.
  • Show the Brainiac Alkali Metals video
  • Play the periodic video of phosphorus.
  • I used to do this at Southern Wayne.
  • First synthesized in 1963.
  • Mg and Se
  • This is what you need to remember.
  • As and P
  • This is what you need to remember.
  • C and Na
  • This is what you need to remember.
  • Ca and Sb
  • Linus Pauling protesting Nuclear testing at the White House. Believed in taking large doses of Vitamin C. He lived until he was 93.
  • This is what you need to remember.
  • Cl and F
  • Cl-1 and Na+1
  • Li2SBaCl2AlBr3Silver ChlorideCadmium Oxide Aluminum Oxide
  • Nickel (II) oxideChromium (III) chlorideTin (IV) chloride or stannic chloride CuBr2Fe2O3CoN
  • FeCl2Fe2S3CuICuBr2HgCl2Hg2Cl2SnF2
  • New chm 151 unit 5 power points sp13 n

    1. 1. CHEMICAL PERIODICITY • PERIODIC TABLE • MENDELEEV • PREDICTION OF PROPERTIES • Chapters 8.4; 9.5; 14.1-14.10 14-1
    2. 2. Goals & Objectives • See the following learning objectives on pages 322-323, 356, 563. • Understand the Concepts: • 8.9-12; 9.13-15; 14.-8, 10, 14, 20, 23. • Master these Skills: 8.6. 14-2
    3. 3. CHEMICAL PERIODICITY • THE PERIODIC TABLE – 1869 Russian chemist Dmitri Mendeleev published a periodic table based on chemical properties of the elements known at the time – 1869 German chemist Julius Lothar Meyer published a similar table based on physical properties – Greater credit was given to Mendeleev because he was able to predict the properties of several undiscovered elements 14-3
    4. 4. Mendeleev’s Periodic Table Elements were grouped in order of atomic mass; if the next known element did not fit, Mendeleev left a space. 14-4
    5. 5. Pictures of Mendeleev & Meyer 14-5
    6. 6. Mendeleev’s Predictions 14-6
    7. 7. The Periodic Law • The properties of the elements are periodic functions of their atomic number • This change is based on the work of British chemist Henry G. J. Moseley, who showed that the order of the periodic table is not based on atomic mass but rather on atomic number. 14-7
    8. 8. Henry Moseley picture • During the first World War, Moseley was killed while serving as a pilot in the British army at the age of 26. Thus a brilliant career was lost to science 14-8
    9. 9. Terminology • • • • • • • • 14-9 Group(family) of element - vertical column Period(row) of elements - horizontal row Group 1 metals - alkali metals Group 2 metals - alkaline earth metals Group 1 + Group 2 - representative metals Group 16 - chalcogens Group 17 - halogens Group 18 - rare, inert or noble gases
    10. 10. Classification of the Elements 14-10
    11. 11. Classification of the Elements Nonmetals Transitions metals 14-11 Post trans. Metals
    12. 12. This is a link to the Element Song. The Elements" (1959) is a song by musical humorist Tom Lehrer, which recites the names of all the chemical elements known at the time of writing, up to number 102, nobelium. It can be found on his albums Tom Lehrer in concert, More Songs by Tom Lehrer and An Evening Wasted with Tom Lehrer. The song is sung to the tune of the Major General's Song from The Pirates of Penzance by Gilbert and Sullivan. 14-12
    13. 13. This is a link to the New Element Song. The New Periodic Table Song (2013) is a song by ASCAP Science, which recites the names of all the chemical elements (in order) including the new elements: Flerovium with the symbol "Fl" and atomic number 114 and Livermorium with the symbol “Lv” and atomic number 116. 14-13
    14. 14. Chapter 14 Periodic Patterns in the Main-Group Elements 14-14
    15. 15. Hydrogen • Hydrogen has a very simple structure: – the nucleus has a single positive charge, and has 1 electron. • Hydrogen is the most abundant element in the universe. • Hydrogen exists as a diatomic gas, H2. – H2 is colorless and odorless with very low melting and boiling points. • H is abundant in combination with oxygen as H2O. 14-15
    16. 16. Hydrogen and Group 1 • Like the Group (1) elements, H has a half-filled valence level. • H is similar to the other Group 1 elements in terms of – ionization energy, – electron affinity, – electronegativity, and – bond energies. 14-16
    17. 17. Hydrogen and the Halogens • Like the halogens or Group (17), hydrogen – exists as a diatomic molecule and – needs only 1 electron to fill its valence shell. • Unlike the halogens – H has a much lower electronegativity than any halogen, – H lacks the three valence e- pairs that halogens have, and – halide ions (X-) are common and stable, but the hydride ion (H-) is rare and reactive. 14-17
    18. 18. Table 14.1 14-18 Trends in Atomic, Physical, and Chemical Properties of the Period 2 Elements.
    19. 19. Table 14.1 14-19 Trends in Atomic, Physical, and Chemical Properties of the Period 2 Elements.
    20. 20. Table 14.1 14-20 Trends in Atomic, Physical, and Chemical Properties of the Period 2 Elements.
    21. 21. Table 14.1 14-21 Trends in Atomic, Physical, and Chemical Properties of the Period 2 Elements.
    22. 22. Table 14.1 Trends in Atomic, Physical, and Chemical Properties of the Period 2 Elements. Trends in atomic radius, ionization energy, and electronegativity across Period 2. 14-22
    23. 23. Group (1): The Alkali Metals Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-23
    24. 24. Properties of the Alkali Metals • Alkali metals are the largest elements in their respective periods and their valence electron configuration is ns1. – The valence e- is relatively far from the nucleus, resulting in weak metallic bonding. • Alkali metals are unusually soft for metals. They can be cut easily with a knife. • Alkali metals have lower melting and boiling points than any other group of metals. • Alkali metals have lower densities than most metals. 14-24
    25. 25. Periodic Properties • • • • • 14-25 Electron configurations Li [He]2s1 Na [Ne]3s1 K [Ar]4s1 Rb [Kr]5s1
    26. 26. Lithium floating in oil floating on water. Alkali metals have low densities. 14-26 Potassium reacting with water. Alkali metals are very reactive.
    27. 27. Demonstration of the Reactivity of Alkali Metals • The following YouTube video shows the reactivity of the alkali metals. • Brainiac Alkali Metals 14-27
    28. 28. Group (2): The Alkaline Earth Metals • The oxides of Group (2) elements form basic solutions and melt at extremely high temperatures. • Group (2) elements have higher ionization energies than Group (1) elements – due to their higher effective nuclear charge and smaller size. • Group (2) elements are strong reducing agents. 14-28
    29. 29. Group (2): The Alkaline Earth Metals Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-29
    30. 30. Group (13): The Boron Family Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-30
    31. 31. Influence of Transition Elements on Group (13) The larger 13 elements have smaller atomic radii and larger ionization energies than electronegativities than expected. These properties influence the physical and chemical behavior of these elements. 14-31
    32. 32. Group (14): The Carbon Family Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-32
    33. 33. Allotropes Allotropes are different crystalline or molecular forms of the same element. One allotrope of a particular element is usually more stable than another at a particular temperature and pressure. Carbon has several allotropes, including graphite, diamond, and fullerenes. Tin exhibits two allotropes; white β-tin and gray α-tin. 14-33
    34. 34. Figure 14.9 14-34 Phase diagram of carbon.
    35. 35. Figure 14.10 Crystalline buckminsterfullerene and a buckyball (A) and nanotubes (B). Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Crystals of buckminsterfullerene (C60) Nanotubes 14-35
    36. 36. Carbon in Organic Chemistry The large number and wide variety of organic compounds is due to the ability of C to bond to itself, and to form multiple bonds. Catenation is the process whereby carbon bonds to itself to form stable chains, branches, and rings. Since C is small, the C-C bond is short enough to allow effective side-to-side overlap of p orbitals. C readily forms double and triple bonds. 14-36
    37. 37. Figure 14.12 Three of the several million known organic compounds of carbon. Lysine, one of 20 amino acids that occur in proteins 14-37
    38. 38. Inorganic Compounds of Carbon Carbon bond with oxygen to form carbonates. Metal carbonates such as CaCO3 are abundant in minerals. Carbon forms two common gaseous oxides, CO and CO2, which are molecular. Other Group (14) elements form network-covalent or ionic oxides. Carbon halides have major uses as solvents and in structural plastics. 14-38
    39. 39. Figure 14.13 Freon-12 (CCl2F2), a chlorofluorocarbon. Chlorofluorocarbons (CFC’s or Freons) are chemically and thermally stable, nontoxic, and nonflammable. They are excellent cleaners, refrigerants, and propellants, but they decompose extremely slowly near the Earth’s surface. They readily enter the stratosphere, where UV radiation causes them to release free Cl atoms that damage the ozone layer. 14-39
    40. 40. Group (15) Elements • Nitrogen is a diatomic gas (N2) with a very low boiling point, due to its very weak intermolecular forces. • Phosphorus exists most commonly as tetrahedral P4 molecules. It has stronger dispersion forces than N2. • Arsenic exists as extended sheets of As atoms covalently bonded together. The covalent network structure gives it a high melting point. • Antimony also has a covalent network structure. • Bismuth has metallic bonding. Its melting point is lower than that of As or Sb. 14-40
    41. 41. Group (15): The Nitrogen Family Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-41
    42. 42. Figure 14.16 Two allotropes of phosphorous. White phosphorous (P4) Strained bonds in P4 Red phosphorous 14-42
    43. 43. Periodicvideos.com • This is the periodic video for Phosphorus. • Phosphorus Video 14-43
    44. 44. Patterns of Behavior in Group (15) • N gains 3 electrons to form the anion N3-, but only in compounds with active metals. • The higher elements in the group are metallic and lose electrons to form cations. • Oxides change from acidic to amphoteric to basic as you move down the group. • All Group 5A(15) elements form gaseous hydrides with the formula EH3. – All except NH3 are extremely reactive and toxic. 14-44
    45. 45. Oxides of Nitrogen • Nitrogen forms six stable oxides. Hf for all six oxides is positive because of the great strength of the NΞN bond. • NO is produced by the oxidation of ammonia: – 4NH3(g) + 5O2(g) → 4NO(g) +6H2O(g) – This is the first step in the production of nitric acid. • NO is converted to 2 other oxides by heating: 3NO(g) Δ N2O(g) + NO2(g) – This type of redox reaction is called disproportionation. • NO2 is a component of photochemical smog. 14-45
    46. 46. Table 14.3 14-46 Structures and Properties of the Nitrogen Oxides
    47. 47. Group (16) Elements • Oxygen, like nitrogen, occurs as a low-boiling diatomic gas, O2. • Sulfur, like phosphorus, occurs as a polyatomic molecular solid. • Selenium, like arsenic, commonly occurs as a gray metalloid. • Tellurium, like antimony, displays network covalent bonding. • Polonium, like bismuth, has a metallic crystal structure. 14-47
    48. 48. Group (16): The Oxygen Family Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-48
    49. 49. Allotropes in the Oxygen Family Oxygen has two allotropes: - O2, which is essential to life, and - O3 or ozone, which is poisonous. Sulfur has more than 10 different forms, due to the ability of S to catenate. S–S bond lengths and bond angles may vary greatly. Selenium has several allotropes, some consisting of crown-shaped Se8 molecules. 14-49
    50. 50. Figure 14.20 The cyclo-S8 molecule. top view side view At room temperature, the sulfur molecule is a crown-shaped ring of eight atoms. The most stable S allotrope is orthorhombic α-S8, which consists of cyclo-S8. 14-50
    51. 51. Hydrides of the Oxygen Family • Oxygen forms two hydrides: – water (H2O) and hydrogen peroxide (H2O2). – H2O2 contains oxygen in a -1 oxidation state. • The hydrides of the other 16 elements are foul-smelling, poisonous gases. – H2S forms naturally in swamps from the breakdown of organic matter and is as toxic as HCN. • H2O and H2O2 can form H bonds, and therefore have higher melting and boiling points than other H2E compounds. • Hydride bond angles decrease and bond lengths increase down the group. 14-51
    52. 52. Halides of the Oxygen Family Except for O, the Group 16 elements form a wide range of halides. Their structure and reactivity patterns depend on the sizes of the central atom and the surrounding halogens. As the central atom becomes larger, the halides become more stable. 14-52
    53. 53. Highlights of Sulfur Chemistry • Sulfur forms two important oxides: – SO2 has S in its +4 oxidation state. It is a colorless, choking gas that forms when S, H2S or a metal sulfide burns in air. – SO3 has S in the +6 oxidation state. • Sulfur forms two important oxoacids. – Sulfurous acid (H2SO3) is a weak acid with two acidic protons. – Sulfuric acid (H2SO4) is a strong acid, and is an important industrial chemical. It is an excellent dehydrating agent. 14-53
    54. 54. Figure 14.21 The dehydration of sugar by sulfuric acid. 14-54
    55. 55. 14-55
    56. 56. Group (17): The Halogens Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-56
    57. 57. Reactivity of the Halogens A halogen atom needs only one electron to fill its valence shell. Halogens are therefore very reactive elements. The halogens display a wide range of electronegativities, but all are electronegative enough to behave as nonmetals. A halogen will either - gain one electron to form a halide anion or - share an electron pair with a nonmetal atom. The reactivity of the halogens decreases down the group, reflecting the decrease in electronegativity. 14-57
    58. 58. Group (18): The Noble Gases Family Portrait KEY ATOMIC PROPERTIES, PHYSICAL PROPERTIES, AND REACTIONS Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14-58
    59. 59. Noble Gases • Noble gases have a full valence shell. • The noble gases are the smallest elements in their respective periods, with the highest ionization energies. • Atomic size increases down the group and IE decreases. • Noble gases have very low melting and boiling points. • Only Kr, Xe, and Rn are known to form compounds. – Xe is the most reactive noble gas and exhibits all even oxidation states from +2 to +8. 14-59
    60. 60. Figure 14.26 14-60 Crystals of xenon tetrafluoride (Xe(F4).
    61. 61. Chapter 8 Electron Configuration and Chemical Periodicity 14-61
    62. 62. Periodic Properties • Electronic configurations s p d f 14-62 f
    63. 63. Electron Configurations 14-63
    64. 64. Electron Configuration • Give the symbol for the element having the outermost electron configuration 3s2 • Give the symbol for the element having the outermost electron configuration 4p4 14-64
    65. 65. 14-65
    66. 66. Trends in Atomic Size Atomic size increases as the principal quantum number n increases. As n increases, the probability that the outer electrons will be further from the nucleus increases. Atomic size decreases as the effective nuclear charge Zeff increases. As Zeff increases, the outer electrons are pulled closer to the nucleus. For main group elements: atomic size increases down a group in the periodic table and decreases across a period. 14-66
    67. 67. Figure 8.13 Atomic radii of the maingroup and transition elements. 14-67
    68. 68. Figure 8.14 14-68 Periodicity of atomic radius.
    69. 69. Sample Problem 8.3 PROBLEM: Ranking Elements by Atomic Size Using only the periodic table (not Figure 8.15), rank each set of main-group elements in order of decreasing atomic size: (a) Ca, Mg, Sr (b) K, Ga, Ca (c) Br, Rb, Kr (d) Sr, Ca, Rb PLAN: Locate each element on the periodic table. Main-group elements increase in size down a group and decrease in size across the period. 14-69
    70. 70. Sample Problem 8.3 SOLUTION: (a) Sr > Ca > Mg Ca, Mg, and Sr are in Group 2A. Size increases down the group. (b) K > Ca > Ga K, Ga, and Ca are all in Period 4. Size decreases across the period. (c) Rb > Br > Kr Rb is the largest because it has one more energy level than the other elements. Kr is smaller than Br because Kr is further to the right in the same period. (d) Rb > Sr > Ca Ca is the smallest because it has one fewer energy level. Sr is smaller than Rb because it is smaller to the right in the same period. 14-70
    71. 71. Atomic Radii size decreases 14-71
    72. 72. Atomic Radii • Give the symbol for the larger of the two atoms As or N • Give the symbol for the atom having the smaller radius of Na or P 14-72
    73. 73. Ionization Energy (IE) • The energy in kilojoules required for the complete removal of one mole of electrons from one mole of gaseous atoms or ions • Pulling an electron away from the nucleus requires energy to overcome the attraction of the nucleus. 14-73
    74. 74. Trends in Ionization Energy Ionization energy (IE) is the energy required for the complete removal of 1 mol of electrons from 1 mol of gaseous atoms or ions. Atoms with a low IE tend to form cations. Atoms with a high IE tend to form anions (except the noble gases). Ionization energy tends to decrease down a group and increase across a period. 14-74
    75. 75. Figure 8.15 14-75 Periodicity of first ionization energy (IE1).
    76. 76. Figure 8.16 14-76 First ionization energies of the main-group elements.
    77. 77. Ionization Energy IE increases 14-77
    78. 78. Ionization Energy 14-78
    79. 79. Ionization Energy 14-79
    80. 80. Sample Problem 8.4 Ranking Elements by First Ionization Energy PROBLEM: Using the periodic table only, rank the elements in each of the following sets in order of decreasing IE1: (a) Kr, He, Ar (c) K, Ca, Rb (b) Sb, Te, Sn (d) I, Xe, Cs PLAN: Find each element on the periodic table. IE1 generally decreases down a group and increases across a period. SOLUTION: (a) He > Ar > Kr Kr, He, and Ar are in Group 8A. IE1 decreases down the group. 14-80
    81. 81. Sample Problem 8.4 SOLUTION: (b) Te > Sb > Sn Sb, Te, and Sn are in Period 5. IE1 increases across a period. (c) Ca > K > Rb K has a higher IE1 than Rb because K is higher up in Group 1A. Ca has a higher IE1 than K because Ca is further to the right in Period 4. (d) Xe > I > Cs Xe has a higher IE1 than I because Xe is further to the right in the same period. Cs has a lower IE1 than I because it is further to the left in a higher period. 14-81
    82. 82. Ionization Energy • Give the symbol for the element in the same group as Sn having the largest IE. • Give the symbol for the element in the same period as Si having the smallest IE. 14-82
    83. 83. Electron Affinity (EA) • Electron Affinity is the energy change in kilojoules accompanying the addition of one mole of electrons to one mole of gaseous atoms or ions. • In most cases, energy is released when the first electron is added because it is attracted to the atoms nuclear charge. 14-83
    84. 84. Trends in Electron Affinity Electron Affinity (EA) is the energy change that occurs when 1 mol of electrons is added to 1 mol of gaseous atoms or ions. Atoms with a low EA tend to form cations. Atoms with a high EA tend to form anions. The trends in electron affinity are not as regular as those for atomic size or IE. 14-84
    85. 85. Figure 8.18 14-85 Electron affinities of the main-group elements (in kJ/mol).
    86. 86. Behavior Patterns for IE and EA Reactive nonmetals have high IEs and highly negative EAs. These elements attract electrons strongly and tend to form negative ions in ionic compounds. Reactive metals have low IEs and slightly negative EAs. These elements lose electrons easily and tend to form positive ions in ionic compounds. Noble gases have very high IEs and slightly positive EAs. These elements tend to neither lose nor gain electtons. 14-86
    87. 87. Electron Affinity 14-87
    88. 88. Electron Affinity EA increases 14-88
    89. 89. Electron Affinity • Give the symbol for the representative metal in the same period as As having the larger electron affinity. • Give the symbol for the metalloid in the same family as N having the smaller EA. 14-89
    90. 90. Electronegativity (EN) • Electronegativity is the relative ability of a bonded atom to attract the shared electron pair • It was developed over 50 years ago by American Chemist Linus Pauling, who is the only person to win the Nobel Prize in two different categories – Chemistry in 1954 & Peace in 1963. He died in 1994 at age 93. 14-90
    91. 91. Pictures of Linus Pauling 14-91
    92. 92. Trends in Electronegativity The most electronegative element is fluorine. In general electronegativity decreases down a group as atomic size increases. In general electronegativity increases across a period as atomic size decreases. Nonmetals are more electronegative than metals. 14-92
    93. 93. Figure 9.22 14-93 Electronegativity and atomic size.
    94. 94. Electronegativity EN increases 14-94
    95. 95. Electronegativity • Give the symbol for the nonmetal in the same period as Al having the greatest EN. • Give the symbol for the element having the greatest electronegativity. 14-95
    96. 96. Ionic Size vs. Atomic Size Cations are smaller than their parent atoms while anions are larger. Ionic radius increases down a group as n increases. Cation size decreases as charge increases. An isoelectronic series is a series of ions that have the same electron configuration. Within the series, ion size decreases with increasing nuclear charge. 3- > 2- > 1- > 1+ > 2+ > 3+ 14-96
    97. 97. Ionic Radii • Cations are always smaller than their corresponding neutral atoms 14-97
    98. 98. Ionic Radii • Anions are always larger than their corresponding neutral atoms 14-98
    99. 99. Ionic Radii • Give the symbol for the element with the largest ionic radius between Cl and Cl-1. • Give the symbol for the element with the smallest ionic radius between Na and Na+1. 14-99
    100. 100. Binary Compounds   A. Salt of metal cation with only one charge and nonmetal anion MgCl2    14- metal + nonmetal--metal in Group 2 metal + stem of nonmetal + ide magnesium chloride
    101. 101. Binary Compounds  Charges on metals        14- Group 1 +1 Group 2 +2 Aluminum +3 Zinc (Zn) +2 Silver(Ag) +1 Cadmium(Cd) +2 See also Table 2.3 on page 63.
    102. 102. Binary Compounds       14- lithium sulfide barium chloride aluminum bromide AgCl CdO Al2O3
    103. 103. Binary Compounds  B. Salt of metal cation with more than one possible charge and nonmetal anion All metals not covered in A Name must include charge on metal 14-
    104. 104. Binary Compounds   IUPAC System FeCl3, FeCl2   metal + stem of nonmetal+ide charge on metal in Roman numerals   14- iron(III) chloride, iron(II) chloride See also Table 2.4 on page 65.
    105. 105. Binary Compounds       14- NiO CrCl3 SnCl4 Copper (II) bromide Iron (III) oxide Cobalt (III) nitride
    106. 106. Binary Compounds    14- Older system “ic “ suffix designates the higher of two possible charges “ous” suffix designates the lower of two possible charges
    107. 107. Binary Compounds        14- Memorize these four ions for the older system Fe2+ - ferrous Fe3+ - ferric Cu+1 - cuprousCu2+ - cupric Sn2+ - stannous Sn4+ - stannic Hg22+ - mercurous Hg2+ - mercuric See also Table 2.4 on page 65.
    108. 108. Binary Compounds        14- ferrous chloride ferric sulfide cuprous iodide cupric bromide mercuric chloride mercurous chloride stannous fluoride

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