Ionic compounds are formed when oppositely charged ions attract each other. Metals form ionic bonds with nonmetals and crystal lattices. In ionic compounds, the cation is written first followed by the anion to give an electrically neutral compound. Polyatomic ions and oxyanions contain multiple atoms bonded together with oxygen. Metallic bonds are delocalized electrons that are shared between positive metal ions in a crystal lattice.

1. Ionic Compounds andIonic Compounds and
MetalsMetals
Chemistry Chapter 7Chemistry Chapter 7

2. Main IdeasMain Ideas
Ions are formed when atoms gain or lose valenceIons are formed when atoms gain or lose valence
electrons to achieve a stable octet electronelectrons to achieve a stable octet electron
configuration.configuration.
Oppositely charged ion attract each other, formingOppositely charged ion attract each other, forming
electrically neutral ionic compounds.electrically neutral ionic compounds.
In written names and formulas for ionicIn written names and formulas for ionic
compounds, the cation appears first, followed bycompounds, the cation appears first, followed by
the anion.the anion.
Metals form crystal lattices and can be modeled asMetals form crystal lattices and can be modeled as
cations surrounded by a “sea’” of freely movingcations surrounded by a “sea’” of freely moving
valence electrons.valence electrons.

3. Ion FormationIon Formation
Ions are formed when atoms gain or loseIons are formed when atoms gain or lose
valence electrons to achieve a stable octetvalence electrons to achieve a stable octet
electron configuration.electron configuration.
DefineDefine a chemical bond.a chemical bond.
DescribeDescribe the formation of positive andthe formation of positive and
negative ions.negative ions.
RelateRelate ion formation to electronion formation to electron
configuration.configuration.

4. Valence Electrons andValence Electrons and
Chemical BondsChemical Bonds
Chemical BondChemical Bond – is a force that holds two– is a force that holds two
atoms together.atoms together.
They can form between the positive nucleusThey can form between the positive nucleus
of one atom and the negative valenceof one atom and the negative valence
electrons of another atom or between twoelectrons of another atom or between two
oppositely charged ions.oppositely charged ions.

5. Valence Electrons andValence Electrons and
Chemical BondsChemical Bonds
Atom’s try to form the octet – the stableAtom’s try to form the octet – the stable
arrangement of eight valence electrons in thearrangement of eight valence electrons in the
outer energy level – by gaining or losingouter energy level – by gaining or losing
valence electrons.valence electrons.
The transfer of valence electrons betweenThe transfer of valence electrons between
two atoms is based on the ionization energytwo atoms is based on the ionization energy
and electron affinity of the two atoms.and electron affinity of the two atoms.
Noble gases-Noble gases- high ionization energy + lowhigh ionization energy + low
electron affinity = little chemical reactivity.electron affinity = little chemical reactivity.

6. Positive Ion FormationPositive Ion Formation
Cation – positively charged ionCation – positively charged ion
Sodium atom:Sodium atom:
1s1s22
2s2s22
pp66
3s3s11
Sodium ion:Sodium ion:
1s1s22
2s2s22
pp66
= neon= neon

7. Positive Ion FormationPositive Ion Formation
Metal atoms are reactive because they loseMetal atoms are reactive because they lose
valence electrons easily.valence electrons easily.
Group 1: commonly form +1 ionsGroup 1: commonly form +1 ions
Group 2: commonly form +2 ionsGroup 2: commonly form +2 ions
Group 13: sometimes +3 ionsGroup 13: sometimes +3 ions

8. Positive Ion FormationPositive Ion Formation
Transition metal ions have an outer shell of sTransition metal ions have an outer shell of s22
They will lose their s electrons andThey will lose their s electrons and
occasionally a d electron.occasionally a d electron.
Typically form +2 or +3 ions but can formTypically form +2 or +3 ions but can form
greater than +3 ionsgreater than +3 ions

9. Positive Ion FormationPositive Ion Formation
Other relatively stable electron arrangementsOther relatively stable electron arrangements
are referred to as pseudo-noble gasare referred to as pseudo-noble gas
configurations.configurations.
Groups 11-14 will lose electrons to form fullGroups 11-14 will lose electrons to form full
outer shells: s, p, and d.outer shells: s, p, and d.

10. Negative Ion FormationNegative Ion Formation
An anion is a negatively charged ion. (Add “-ide”An anion is a negatively charged ion. (Add “-ide”
to the end of the root atom name.)to the end of the root atom name.)
Nonmetals easily gain electrons.Nonmetals easily gain electrons.
Chlorine atom:Chlorine atom:
1s1s22
2s2s22
pp66
3s3s22
pp55
Chlorine ion:Chlorine ion:
1s1s22
2s2s22
pp66
3s3s22
pp66
= Argon= Argon

11. Negative Ion FormationNegative Ion Formation
Nonmetal ions gain the number of electronsNonmetal ions gain the number of electrons
required to fill an octet.required to fill an octet.
Some nonmetals can gain or lose electrons toSome nonmetals can gain or lose electrons to
complete an octet.complete an octet.
Phosphorus can gain 3 or lose 5Phosphorus can gain 3 or lose 5
Group 15 usually gains 3 electronsGroup 15 usually gains 3 electrons
Group 16 usually gains 2 electronsGroup 16 usually gains 2 electrons
Group 17 usually gains 1 electronGroup 17 usually gains 1 electron

12. Practice ProblemsPractice Problems
page 209 #1-6page 209 #1-6

13. Ionic Bonds and IonicIonic Bonds and Ionic
CompoundsCompounds

14. Ionic Bonds and IonicIonic Bonds and Ionic
CompoundsCompounds
Describe the formation of ionic bonds and theDescribe the formation of ionic bonds and the
structure of ionic compounds.structure of ionic compounds.
Generalize about the strength of ionic bondsGeneralize about the strength of ionic bonds
based on the physical properties of ionicbased on the physical properties of ionic
compounds.compounds.
Categorize ionic bond formation asCategorize ionic bond formation as
exothermic or endothermic.exothermic or endothermic.

15. Ionic BondIonic Bond
Ionic BondIonic Bond is the electrostatic force that holdsis the electrostatic force that holds
oppositely charged particles together.oppositely charged particles together.
Ionic CompoundIonic Compound is a compound that containsis a compound that contains
an ionic bond.an ionic bond.
Ionic bonds between metals and oxygenIonic bonds between metals and oxygen
are calledare called oxidesoxides..
Most other ionic compounds areMost other ionic compounds are
considered salts.considered salts.

16. Binary Ionic CompoundBinary Ionic Compound
Binary Ionic compoundBinary Ionic compound is an ionic compoundis an ionic compound
that contains two different elements.that contains two different elements.
One metallic cation and a nonmetallic anion.One metallic cation and a nonmetallic anion.
Examples: NaCl, MgO, KBr, LiFExamples: NaCl, MgO, KBr, LiF

17. Ionic Bond FormationIonic Bond Formation
Electrons gained and lost in each elementElectrons gained and lost in each element
must be equal. (conservation of electrons)must be equal. (conservation of electrons)
Calcium and FluorineCalcium and Fluorine
Aluminum and OxygenAluminum and Oxygen
Sodium and ChlorineSodium and Chlorine

18. Properties of IonicProperties of Ionic
CompoundsCompounds
Compounds are organized such that a patternCompounds are organized such that a pattern
repeats to balance attraction and repulsionrepeats to balance attraction and repulsion
Total charge of a compound is neutralTotal charge of a compound is neutral
Often highly organizedOften highly organized
Example: NaCl crystalExample: NaCl crystal

19. Crystal LatticeCrystal Lattice
A crystal lattice is a three dimensionalA crystal lattice is a three dimensional
geometric arrangement of particles.geometric arrangement of particles.
Each negative ion is surrounded by aEach negative ion is surrounded by a
positive ion which results in strongpositive ion which results in strong
attractions between ions.attractions between ions.
Size and shape are dependent on relativeSize and shape are dependent on relative
numbers of ions.numbers of ions.

20. Crystal LatticeCrystal Lattice
Physical Properties:Physical Properties:
Characteristics of bond strength – ionicCharacteristics of bond strength – ionic
bonds are relatively strong and take a largebonds are relatively strong and take a large
amount of energy to break.amount of energy to break.
Melting point – highMelting point – high
Boiling point – highBoiling point – high
Hardness of material is high: rigid andHardness of material is high: rigid and
brittle solids.brittle solids.

21. Properties of IonicProperties of Ionic
CompoundsCompounds

22. Crystal LatticeCrystal Lattice
Characteristics of the compound:Characteristics of the compound:
Conducts electricity, conditionallyConducts electricity, conditionally
Ions in solid state ionic compounds are lockedIons in solid state ionic compounds are locked
in place and they do not have free electronsin place and they do not have free electrons
in order to conduct electricity.in order to conduct electricity.
Ionic compounds that are melted or dissolvedIonic compounds that are melted or dissolved
in aqueous solutions have ions that are freein aqueous solutions have ions that are free
to move and therefore do conduct electricityto move and therefore do conduct electricity
Electrolyte – an ionic compound thatElectrolyte – an ionic compound that
conducts electricity in an aqueous solution.conducts electricity in an aqueous solution.

23. Energy and the IonicEnergy and the Ionic
BondBond
Formation of ionic compounds forms aFormation of ionic compounds forms a
more stable system and therefore reducesmore stable system and therefore reduces
the energy required to sustain it.the energy required to sustain it.
Since the creating of bonds lowers energy,Since the creating of bonds lowers energy,
energy is released in the process. Theenergy is released in the process. The
creation of bonds is said to becreation of bonds is said to be Exothermic.Exothermic.
ExothermicExothermic – energy is released during a– energy is released during a
chemical reaction.chemical reaction.

24. Energy and the IonicEnergy and the Ionic
BondBond
Breaking of ionic compounds reduces theBreaking of ionic compounds reduces the
stability of a system and therefore increasesstability of a system and therefore increases
the energy required to sustain it .the energy required to sustain it .
Since the creating of bonds lowers energy, theSince the creating of bonds lowers energy, the
breaking of bonds increases energy andbreaking of bonds increases energy and
therefore it is required for the process.therefore it is required for the process.
EndothermicEndothermic – energy is absorbed during a– energy is absorbed during a
chemical reaction.chemical reaction.

25. Lattice EnergyLattice Energy
Lattice energy is the energy required to separate 1Lattice energy is the energy required to separate 1
mole of the ions of an ionic compound.mole of the ions of an ionic compound.
higher the lattice energy the stronger the bondhigher the lattice energy the stronger the bond
strength.strength.
Directly related to the size of the ions bonded.Directly related to the size of the ions bonded.
smaller ions form compounds more closelysmaller ions form compounds more closely
because attraction increases with decreasedbecause attraction increases with decreased
distance.distance.
Also affected by charge of ionsAlso affected by charge of ions
Higher ion charge typically has higher latticeHigher ion charge typically has higher lattice
energy.energy.

26. Practice ProblemsPractice Problems
Page 217 #12-18Page 217 #12-18

27. Names and FormulasNames and Formulas
for Ionic Compoundsfor Ionic Compounds

28. Names and FormulasNames and Formulas
for Ionic Compoundsfor Ionic Compounds
Relate a formula unit of an ionic compoundRelate a formula unit of an ionic compound
to its composition.to its composition.
Write formulas for ionic compounds andWrite formulas for ionic compounds and
oxyanions.oxyanions.
Apply naming conventions to ionicApply naming conventions to ionic
compounds and oxyanions.compounds and oxyanions.

29. Formulas for IonicFormulas for Ionic
CompoundsCompounds
A standardized system for namingA standardized system for naming
compounds was developed for much thecompounds was developed for much the
same reason as the SI unit system. Thissame reason as the SI unit system. This
serves as a universal naming system forserves as a universal naming system for
communication among the sciencecommunication among the science
community.community.

30. Formula UnitFormula Unit
AA formula unitformula unit is the chemical formula for an ionicis the chemical formula for an ionic
compound and represents the simplest ratio ofcompound and represents the simplest ratio of
ions.ions.
MgClMgCl22 not Mgnot Mg44ClCl88
AA monoatomicmonoatomic ion is a one atom ion.ion is a one atom ion.

31. Oxidation numberOxidation number
Oxidation numberOxidation number (oxidation state) the(oxidation state) the
charge of a monatomic ion.charge of a monatomic ion.

32. Formulas for IonicFormulas for Ionic
CompoundsCompounds
The symbol for the cation is written first withThe symbol for the cation is written first with
the anion second.the anion second.
Subscripts represent the number of atoms ofSubscripts represent the number of atoms of
each element in a compound.each element in a compound.
The total charge must equal zero in an ionicThe total charge must equal zero in an ionic
compound.compound.

33. Practice ProblemsPractice Problems
Page 221 #19-23Page 221 #19-23

34. Polyatomic IonsPolyatomic Ions
Polyatomic ionsPolyatomic ions are made up of more than oneare made up of more than one
atom.atom.
Formulas for polyatomic ionic compoundsFormulas for polyatomic ionic compounds
Charge applies to the entire group of atoms.Charge applies to the entire group of atoms.
Parentheses are used if more than oneParentheses are used if more than one
polyatomic ion is needed to balance apolyatomic ion is needed to balance a
compound.compound.
Do not change subscripts within the ion groupDo not change subscripts within the ion group
Example (NHExample (NH44)O)O

35. Polyatomic IonsPolyatomic Ions

36. OxyanionOxyanion
AnAn oxyanionoxyanion is a polyatomic negative ionis a polyatomic negative ion
composed of an element, usually a nonmetal,composed of an element, usually a nonmetal,
bonded to one or more oxygen.bonded to one or more oxygen.

37. Oxyanion Naming RulesOxyanion Naming Rules

38. Names for Ions andNames for Ions and
Ionic CompoundsIonic Compounds
1.1. Name the cation followed by the anion.Name the cation followed by the anion.
2.2. For monatomic cations, use the elementFor monatomic cations, use the element
name.name.
3.3. For monatomic anions, use the root of theFor monatomic anions, use the root of the
element with the suffix –ide.element with the suffix –ide.

39. Names for Ions andNames for Ions and
Ionic CompoundsIonic Compounds
4.4. Multiple oxidation states are represented by aMultiple oxidation states are represented by a
Roman numeral in paranthesis after the cation.Roman numeral in paranthesis after the cation.
a)a) This applies to transition metals with more thanThis applies to transition metals with more than
one oxidation state and not the Group 1 and 2one oxidation state and not the Group 1 and 2
cations.cations.
b)b) Example: FeO is Iron (II) oxide; FeExample: FeO is Iron (II) oxide; Fe22OO33 Iron (III)Iron (III)
oxide.oxide.
4.4. With a polyatomic ion, name the cation followed byWith a polyatomic ion, name the cation followed by
the name of the polyatomic ion.the name of the polyatomic ion.
a)a) Example: NaOH is sodium hydroxide.Example: NaOH is sodium hydroxide.

40. Problem SolvingProblem Solving

41. Practice ProblemsPractice Problems
page 223 #28-33; page 224 #34-39page 223 #28-33; page 224 #34-39

42. Metallic Bonds and theMetallic Bonds and the
Properties of MetalsProperties of Metals

43. Metallic Bonds and theMetallic Bonds and the
Properties of MetalsProperties of Metals
DescribeDescribe a metallic bond.a metallic bond.
RelateRelate the electron sea model to the physicalthe electron sea model to the physical
properties of metals.properties of metals.
DefineDefine alloys, and categorize them into twoalloys, and categorize them into two
basic types.basic types.

44. MetalsMetals
Metals are not ionic but share severalMetals are not ionic but share several
properties with ionic compounds.properties with ionic compounds.
Metals also form lattices in the solid state,Metals also form lattices in the solid state,
where 8 to 12 other atoms closely surroundwhere 8 to 12 other atoms closely surround
each metal atom.each metal atom.
Within the crowded lattice, the outer energyWithin the crowded lattice, the outer energy
levels of metal atoms overlap.levels of metal atoms overlap.

45. Electron Sea ModelElectron Sea Model
The electron sea model proposes that all metalThe electron sea model proposes that all metal
atoms in a metallic solid contribute theiratoms in a metallic solid contribute their
valence electrons to form a "sea" of electron.valence electrons to form a "sea" of electron.
• The electrons are free to move around andThe electrons are free to move around and
are referred to as delocalized electrons,are referred to as delocalized electrons,
forming a metallic cation.forming a metallic cation.

46. Metallic BondsMetallic Bonds
A metallic bondA metallic bond is the attraction of an metallicis the attraction of an metallic
cation for delocalized electronscation for delocalized electrons

47. Properties of MetalsProperties of Metals
• Boiling points are much more extreme thanBoiling points are much more extreme than
melting points because of the energymelting points because of the energy
required to separate atoms from the groupsrequired to separate atoms from the groups
of cations and electrons.of cations and electrons.

48. Properties of MetalsProperties of Metals
• Metals are malleable because they can beMetals are malleable because they can be
hammered into sheets.hammered into sheets.
• Metals are ductile because they can be drawnMetals are ductile because they can be drawn
into wires.into wires.

49. Properties of MetalsProperties of Metals
• Mobile electrons around cations make metalsMobile electrons around cations make metals
good conductors of electricity and heat.good conductors of electricity and heat.
• As the number of delocalized electronsAs the number of delocalized electrons
increases, so does hardness and strength.increases, so does hardness and strength.

50. Metal AlloysMetal Alloys
An alloy is a mixture of elements that hasAn alloy is a mixture of elements that has
metallic properties.metallic properties.
• The properties of alloys differ from theThe properties of alloys differ from the
elements they contain.elements they contain.

51. Metal AlloysMetal Alloys

52. Metal AlloysMetal Alloys
• SubstitutionalSubstitutional alloys are formed when somealloys are formed when some
atoms in the original metallic solid areatoms in the original metallic solid are
replaced by other metals of similar atomicreplaced by other metals of similar atomic
structure.structure.
• InterstitialInterstitial alloys are formed when smallalloys are formed when small
holes in a metallic crystal are filled withholes in a metallic crystal are filled with
smaller atoms.smaller atoms.

53. Practice ProblemsPractice Problems
• Page 228 #40-43Page 228 #40-43

54. Study GuideStudy Guide
Key ConceptsKey Concepts

55. Key ConceptsKey Concepts
• A chemical bond is the force that holds two atomsA chemical bond is the force that holds two atoms
together.together.
• Some atoms form ions to gain stability. ThisSome atoms form ions to gain stability. This
stable configuration involves a complete outerstable configuration involves a complete outer
energy level, usually consisting of eight valenceenergy level, usually consisting of eight valence
electrons.electrons.
• Ions are formed by the loss or gain of valenceIons are formed by the loss or gain of valence
electrons.electrons.

56. Key ConceptsKey Concepts
• The number of protons remains unchanged duringThe number of protons remains unchanged during
ion formation.ion formation.
• Ionic compounds contain ionic bonds formed byIonic compounds contain ionic bonds formed by
the attraction of oppositely charged ions.the attraction of oppositely charged ions.
• Ions in an ionic compound are arranged in aIons in an ionic compound are arranged in a
repeating pattern known as a crystal latticerepeating pattern known as a crystal lattice

57. Key ConceptsKey Concepts
• Ionic compound properties are related toIonic compound properties are related to
ionic bond strength.ionic bond strength.
• Ionic compounds are electrolytes; theyIonic compounds are electrolytes; they
conduct an electric current in the liquid phaseconduct an electric current in the liquid phase
and in aqueous solution.and in aqueous solution.
• Lattice energy is the energy needed toLattice energy is the energy needed to
remove 1 mol of ions from its crystal lattice.remove 1 mol of ions from its crystal lattice.

58. Key ConceptsKey Concepts
• A formula unit gives the ratio of cations toA formula unit gives the ratio of cations to
anions in the ionic compound.anions in the ionic compound.
• A monatomic ion is formed from one atom.A monatomic ion is formed from one atom.
The charge of a monatomic ion is its oxidationThe charge of a monatomic ion is its oxidation
number.number.
• Roman numerals indicate the oxidationRoman numerals indicate the oxidation
number of cations having multiple possiblenumber of cations having multiple possible
oxidation states.oxidation states.

59. Key ConceptsKey Concepts
• Polyatomic ions consist of more than onePolyatomic ions consist of more than one
atom and act as a single unit.atom and act as a single unit.
• To indicate more than one polyatomic ion in aTo indicate more than one polyatomic ion in a
chemical formula, place parentheses aroundchemical formula, place parentheses around
the polyatomic ion and use a subscript.the polyatomic ion and use a subscript.
• A metallic bond forms when metal cationsA metallic bond forms when metal cations
attract freely moving, delocalized valenceattract freely moving, delocalized valence
electrons.electrons.

60. Key ConceptsKey Concepts
• In the electron sea model, electrons moveIn the electron sea model, electrons move
through the metallic crystal and are not heldthrough the metallic crystal and are not held
by any particular atom.by any particular atom.
• The electron sea model explains the physicalThe electron sea model explains the physical
properties of metallic solids.properties of metallic solids.
• Metal alloys are formed when a metal isMetal alloys are formed when a metal is
mixed with one or more other elements.mixed with one or more other elements.

61. QuestionsQuestions
Cations form when atoms _______ electrons.Cations form when atoms _______ electrons.
A.A. gaingain
B.B. loselose
C.C. chargecharge
D.D. delocalizedelocalize

62. QuestionsQuestions
What is the repeating pattern of atoms in an ionic solidWhat is the repeating pattern of atoms in an ionic solid
called?called?
A.A. crystal latticecrystal lattice
B.B. ionic latticeionic lattice
C.C. energy latticeenergy lattice
D.D. ionic bondingionic bonding

63. QuestionsQuestions
Give the name of the following: NaClOGive the name of the following: NaClO44
A.A. sodium hypochloritesodium hypochlorite
B.B. sodium chloritesodium chlorite
C.C. sodium chloratesodium chlorate
D.D. sodium perchloratesodium perchlorate

64. QuestionsQuestions
As the distance between ions in an ionic bond is shortened,As the distance between ions in an ionic bond is shortened,
A.A. the energy to break the bond decreases.the energy to break the bond decreases.
B.B. the electrostatic attraction decreases.the electrostatic attraction decreases.
C.C. the electrostatic attraction increases.the electrostatic attraction increases.
D.D. the ionic bond changes to a metallic bond.the ionic bond changes to a metallic bond.

65. QuestionsQuestions
An alloy is what type of substance?An alloy is what type of substance?
A.A. heterogeneous mixtureheterogeneous mixture
B.B. compoundcompound
C.C. mixture of elementsmixture of elements
D.D. elementelement

66. QuestionsQuestions
Which is NOT true about metallic solids?Which is NOT true about metallic solids?
A.A. Metals are shiny.Metals are shiny.
B.B. Metals are good conductors of heat and electricity.Metals are good conductors of heat and electricity.
C.C. Metals are ductile.Metals are ductile.
D.D. Metals have relatively low boiling points.Metals have relatively low boiling points.

67. QuestionsQuestions
Electrons in an atom’s outer most energy level areElectrons in an atom’s outer most energy level are
referred to as what?referred to as what?
A.A. ionsions
B.B. cationscations
C.C. valence electronsvalence electrons
D.D. noble-gas electronsnoble-gas electrons

68. QuestionsQuestions
What is the oxidation state of copper in Cu(II)ClWhat is the oxidation state of copper in Cu(II)Cl22??
A.A. 1+1+
B.B. 2+2+
C.C. 2–2–
D.D. unable to determineunable to determine

69. QuestionsQuestions
Which elements naturally occur with a full octet ofWhich elements naturally occur with a full octet of
valence electrons?valence electrons?
A.A. alkali metalsalkali metals
B.B. alkali earth metalsalkali earth metals
C.C. halogenshalogens
D.D. noble gasesnoble gases

70. QuestionsQuestions
How many electrons are in a full octet?How many electrons are in a full octet?
A.A. 1010
B.B. 88
C.C. 66
D.D. 44

71. The EndThe End