Ionic Bonding and Naming
Chapter 7 and 9
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• SC1 Students will analyze the nature of matter and its
classifications.
• SC1.b. Identify substances based on chemical and physical
properties.
• SC1.c. Predict formulas for stable ionic compounds
(binary and tertiary) based on balance of charges.
• SC1.d. Use IUPAC nomenclature for both chemical names
and formulas:
• SC1.d.1 Ionic compounds (Binary and tertiary)
• SC1.d.3 Acidic compounds (Binary and tertiary)
• SC3.e. Compare and contrast types of chemical bonds (i.e.
ionic, covalent).
• SC3.b. Use the orbital configuration of neutral atoms to
explain its effect on the atom’s chemical properties.
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What do we already know?
• Protons determine the IDENTINTY of the element
• Valance Electrons determine the CHEMICAL
properties of an element.
• Valance electrons are the electrons in the OUTER
ENERGY level
• For representative elements look at the group
number to determine the number of valance
electrons
• Elements lose or gain electrons to achieve a full
outer energy level (full OCTET)
– Metals form CATIONS by losing electrons
– Nonmetals form ANIONS by gaining electrons
3
The Octet Rule
• Octet rule stated that in forming compounds
atoms tend to achieve the electron configuration
of a noble gas.
• An octet is a set of eight electrons
• Atoms of metals tend to lose their valence
electrons leaving a complete octet in the nextlowest energy level.
• Atoms of some nonmetals tend to gain electrons
or to share electrons with another nonmetals to
achieve a complete octet.
4
Lewis Structure
• Electron dot structures (Lewis dot structure) are
diagram that show the valence electrons at dots.
• Each valance electron is represented with a dot
• Put one dot on each side of the symbol before
putting two on one side.
• Examples
1.Carbon
2.Calcium
3.Chlorine
4.Argon
4 valance e2 valance e7 valance e8 valance e-
C
Ca
Cl
Ar
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Formation of Ionic Compounds
• Ionic compounds are compounds composed of
cations and anions.
• Although they are compounds of ions, ionic
compounds are electrically neutral.
– Ionic bonds are the electrostatic forces that hold ions
together in ionic compounds. They occur due to the
transfer of electrons
– Chemical formula shows the kinds and numbers of
atoms in the smallest representative unit of a
substance.
– Formula unit is the lowest whole-number ratio of ions
in an ionic compound
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Formula Writing
1. When writing formulas the MOST METALIC
element is written first
– Ionic bonds occur between METALS and
NONMETALS so the metal is ALWAYS written FIRST.
2. Determine the ion that the elements will form
3. Balance charges
– Can switch charges and reduce if necessary
– Or can use the following equation:
# of metal x charge of metal + # of nonmetal x charge of nonmetal = 0
atoms
atoms
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Formula Writing
• Practice 1: Oxygen and Sodium
1. Sodium is metal so it MUST be written first
2. Na forms +1 ion and O forms -2 ion
3. Na+1 O-2 switching charges gives Na2O
(# metal) +1 +(#nonmetal) -2 = 0 solve
(2) +1 +(1) -2 = 0 gives Na2O
NOTE: The subscript of 1 is NOT written
• Practice 2: Nitrogen and Aluminum
1. Aluminum is metal so it MUST be written first
2. Al forms +3 ion and N forms -3 ion
3. Al+3 N-3 switching charges gives AlN (must reduce)
(# metal) +3 +(#nonmetal) -3 = 0 solve
(1) +3 +(1) -3 = 0 gives AlN
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Formula Writing
• Practice 3: Calcium and Carbon
1. Calcium is metal so it MUST be written first
2. Ca forms +2 ion and C forms -4 ion
3. Ca+2 C-4 switching charges gives Ca2C
(# metal) +2 +(#nonmetal) -4 = 0 solve
(2) +2 +(1) -4 = 0 gives Ca2C
• Practice 4: Barium and Phosphate (PO4-3)
1. Barium is metal so it MUST be written first
2. Ba forms +2 ion and PO4 is a -3 ion
3. Al+2 PO4-3 switching charges gives Al3(PO4)2
(# metal) +2 +(#nonmetal) -3 = 0 solve
(3) +2 +(2) -3 = 0 gives Al3(PO4)2
MUST USE parenthesis to show having 2 phosphate
molecules.
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Ionic Naming – Type 1 metals
Type 1 metals are metals that form only 1 oxidation
state.
They are found in groups 1, 2, & 13 in addition to Zn+2,
Cd+2, and Ag+1
1. Determine the Cation and the Anion
2. If the cation is from a representative element write
its name
3. The anion is a:
a. Polyatomic ion write it’s special name
b. Single nonmetal element write its root name followed by
“ide”
4. write both parts of name side by side
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Ionic Naming – Type 1
• Example 1: Ca3N2
1.
2.
3.
4.
Calcium is the cation, nitrogen is anion
Calcium stays calcium
Nitrogen is NOT a polyatomic so it becomes Nitride
Ca3N2 is called calcium nitride
• Example 1: Ca3(PO4)2
1.
2.
3.
4.
Calcium is the cation, phosphate is anion
Calcium stays calcium
Phosphate is a polyatomic so it’s name is phosphate
Ca3(PO4)2 is called calcium phosphate
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Ionic Naming – Type 1
• Practice
1. KCl
2. AlCl3
3. Ca2C
4. InN
5. Rb3PO3
6. Al(OH)3
7. In2(SO3)3
8. (NH4)3Br
• Practice
1. Potassium chloride
2. Aluminum chloride
3. Calcium carbide
4. Indium nitride
5. Rubidium phosphite
6. Aluminum hydroxide
7. Indium sulfite
8. ** Ammonium bromide
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Ionic Naming – Type 2 metals
• Most transition metals have the ability to borrow
electrons from other orbitals and can form ions with
different charges.
• Metals in group 14 also have multiple oxidation
states. +2 or +4
• Example: Iron can from a +3 or +4 cation,
copper can from a +2 or +1 ion
• Not ALL transition metal do this but MOST do so
when we name the compound we have to state the
charge of the metal ion
• EXCEPTIONS: three transition metals that you MUST
memorize the following: Zn+2, Cd+2, Ag+1 as they do
NOT need roman numerals
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Ionic Naming – Type 2 Metals
1. Determine the Cation and the Anion
2. If the cation is from a transition element write
its name followed by a roman numeral to show
the charge of the metal ion.
3. The anion is a:
a. Polyatomic ion write it’s special name
b. Single nonmetal element write its root name
followed by “ide”
4. write both parts of name side by side
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Ionic Naming – Type 2
• Common Roman numerals you MUST
KNOW
1. I
6. VI **
2. II
7. VII
3. III
8. VIII
4. IV **
9. IX
5. V
10. X
** commonly confused by students
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Ionic Naming – Type 2
• Example 1: FeO
1. Fe is cation and O is anion
2. since Oxygen has a -2 charge Fe MUST have a +2 so it is
Iron (II)
3. O is NOT a polyatomic so it becomes Oxide
4. FeO is Iron (II) Oxide
• Example 2: Fe2O3
1. Fe is cation and O is anion
2. since Oxygen has a -2 charge Fe MUST have a +3 so it is
Iron (III)
3. O is NOT a polyatomic so it becomes Oxide
4. FeO is Iron (III) Oxide
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Ionic Naming – Type 2
• Example 3: FePO4
1. Fe is cation and PO4 is anion
2. since PO4 has a -3 charge Fe MUST have a +3 so it is Iron
(III)
3. PO4 is a polyatomic so it is phosphate
4. FeO is Iron (III) Phosphate
• Example 4: Ag2O
1. Ag is cation and O is anion
2. Ag is an exception and only forms a +1 ion so is Silver
3. O is NOT a polyatomic so it becomes Oxide
4. Ag2O is Sliver Oxide
Remember Zn+2, Cd+2, Ag+1 do NOT need roman numerals
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Ionic Names to formula
1. Use the name to determine the ions of the
elements (or polyatomic) in compound
2. Write the ions for each element
3. Balance charges using either method(reduce if
necessary)
– Chemical formulas for COMPOUNDS do NOT have
charges!!
– The number of atoms MUST be shown as a subscript.
– REMEMBER the size and the shape of the letters
matter when writing chemical formulas: COS and CoS
are two different things
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Ionic Names to Formulas
• Examples
• Examples
1. Strontium Sulfide
• Sr+2 S-2
• SrS
2. Magnesium Cyanide
4. Zinc Oxide
•
•
Mg +2 CN-1
Mg(CN)2
3. Potassium Phosphide
•
•
K+1 P+3
K3P
•
•
Zn+1 O-2
Zn2O
5. Cobalt (II) Oxide
•
•
Co+2 O-2
CoO
6. Manganese (IV) Sulfate
•
•
Mn+4 S-2
MnS2
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Formation of Ionic Compounds
• Metals lose their electrons to nonmetals
• The opposite charges attract and form an ionic
bond
Na + Cl →Na + Cl →Na+1 + Cl-1 → NaCl
name is: sodium chloride
Mg + S →Mg + S →Mg+2 + S-2 → MgS
name is: Magnesium Sulfide
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Properties of Ionic Compounds
• Ionic compounds form by the TRANSFER of electrons
• Most ionic compounds are crystalline solids at room
temperature.
• Ions in the crystals are arranged in repeating threedimensional patterns.
• The large attractive forces result in very stable structures
• Ionic compounds generally have high melting points.
• Ionic compounds can conduct an electric current when
melted or dissolved in water
• The ion movement allows electricity to flow between
electrodes
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Metallic Bonds and Metallic Properties
• The valence electrons of metal atoms can be
modeled as a sea of electrons.
• Metallic bonds consist of the attraction of the freefloating valence electrons for the positively charged
metal ions.
• the sea-of-electrons models explains many physical
properties of metals
• metals are good conductors of electric current
because electrons can flow freely in them
• metals are malleable (can be hammered or forced
into shapes.)
• metals are ductile (can be drawn into wires)
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Alloys
• metal atoms are arranged in very compact and
orderly patterns
• alloys are mixtures composed of two or more
elements, at least of one which is metal
• alloys are important because their properties
are superior to those of their components
elements.
• Bronze alloy is made of copper and iron
• Steel alloys are made of iron and carbon with
additional elements.
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