BONDING
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Learning Objectives
After completing this unit of study, you should be able to:
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Chemical bonds are formed when valence electrons are shared between two atoms, transferred
from one atom to another, or mobile within a network of atoms.
An atom needs to acquire a noble gas configuration (8 valence electrons with the exception of
Helium, two valence electrons) in order to become stable.
An atom becomes stable by forming a chemical bond.
Ion a multiple covalent bond, more than one pair of electrons is shared.
Lewis structures show valence electron arrangements in elements, compounds, and ions.
Electronegativity is a measure of how strongly an atom attracts electrons in a bond.
Difference in electronegativity is an indication of the degree of polarity of a bond.
Metals tend to react with nonmetals to form an ionic compound.
Nonmetals tend to react with other nonmetals to form molecular compounds
Ionic compounds containing polyatomic ions have both ionic and covalent bonding.
Substances can be classified as metallic, ionic and molecular based on chemical and physical
properties.
Two categories of compounds are molecular (covalent) and ionic.
Physical properties like conductivity, solubility, malleability, hardness, melting point and boiling
point can be explained in terms of bonding and internal forces of attractions.
Molecular polarity can be determined by the shape of the molecule and the distribution of charge.
Examples of molecules, which are symmetrical and therefore nonpolar, are CO2, CH4, and diatomic
elements.
Examples of molecules, which are asymmetrical and therefore polar, are HCl, NH3, H2O.
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Vocabulary
Use your review book to write the definitions for each term listed below:
1. Element
2. Compound
3. Ion
4. Chemical Bond
5. Potential Energy
6. Valence Electron
7. Octet Rule
8. Lewis Dot Structure
9. Ionic Bond
10. Covalent Bond
11. Metallic Bond
12. Noble Gas Configuration
13. Double Covalent Bond
14. Triple Covalent Bond
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15. Electronegativity
16. Polar Covalent Bond
17. Nonpolar Covalent Bond
18. Ionic Compound
19. Molecular Compound
20. Polyatomic Ion
21. Polar Molecule
22. Nonpolar Molecule
23. Hydrogen Bond
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Name ________________________________________
Date__________________________
Use Review Book Pages 98-116
Period_________________________
1. What are the forces that hold atoms together in a compound? (p.98)
2. Breaking of chemical bonds is an exothermic/endothermic (circle one) process.
3. The formation of chemical bonds is an exothermic/endothermic (circle one) process.
4. Energy is always released in forming a bond. Why does the greater the energy released in forming a bond result in
a more stable bond? (HINT: think about reversible reactions)
5. Which of the following reactions will is more stable? Support your answer.
Rxn 1: B + C  BC + 100J
Rxn 2: K + L  KL + 400 J
6. The tendency for atoms to react in order to obtain 8 valence electrons is known as the ______________ Rule.
(p103)
7. Why are Noble Gases relatively unreactive (except _____________ & _____________ w/ _______________)?
8. Complete the following chart using the information found on pp104 & 108:
Bond Type
Type of Elements
(M, SM, NM)
Share or Transfer
electrons?
EN
Example Substances
Covalent
Ionic
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Name ________________________________________
Date__________________________
Use Review Book Pages 98-116
Period_________________________
1. What is an Ion?
2. How are ions formed?
3. Explain how Ionic Bonds are formed:
4. Ionic bonds are formed by the transfer/sharing (circle one) of electrons.
5. Complete the following based on table 6-1 found on p109:
When metals react they:
When nonmetals react they:
1.
1.
2.
2.
3.
3.
4.
4.
6. Metals and nonmetals gain or lose electrons in order to achieve a __________________ __________ electron
configuration.
7. Complete the following table based on the information provided in figure 6-13:
Element
Atom’s Electron
Configuration
# valence
electrons
Will it gain or lose
electrons & how
many?
Ionic symbol &
charge
Ion’s electron
configuration
OXYGEN
FLOURINE
NEON
SODIUM
MAGNESIUM
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8. List the properties of ionic solids (table 6-2)
Melting Point _________________
Boiling Point __________________
Hardness _____________________
Conductivity in Solid ______________________ Liquid __________________ Aqueous _________________
9. On which reference table are polyatomic ions located? _________________
10. What 2 types of bonds are found within all compounds with polyatomic ions? ______________ & ____________
11. Complete the following by correctly writing the formula of each commonly used polyatomic ions (as in the
example shown):
Polyatomic Ion Name
Hydronium
Polyatomic Ion formula
(H3O)+
Polyatomic Ion Name
Polyatomic Ion formula
Nitrate
Ammonium
Peroxide
Acetate
Hydroxide
Carbonate
Phosphate
Chromate
Sulfite
Nitrite
Sulfate
12. As the electronegativity difference between 2 elements increases, ionic character increases/decreases (circle one).
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Name ________________________________________
Date__________________________
Use Review Book Pages 27-32
Period_________________________
1. (p27) ________________________use chemical symbols and numbers to show both qualitative and quantitative
information about a substance. Subscripts (located to the _______________ and _______________ the symbol) tell
the ______________________of atoms of each element in a compound.
2. Complete the following based on the information found on p 28 of your review book:
Type of formula
Definition
Type of Bonding
Example
Empirical Formula
Molecular Formula
3. Atoms and compounds are electrically _________________________, having equal number of positive and
negative charges.
4. An ion with more protons than neutrons will be _________________________charged, while an ion with more
electrons than protons will be _____________________________charged. Positively charged ions will attract
_______________________________________in a ratio that produces ____________________compound.
5. Common oxidation states are located in the _________________________________ corner of the element’s box
on the periodic table.
6. How do compounds achieve neutrality?
7. Why does a 1:1 ratio in NaCl produce a neutral compound, but a 1:1 ratio in the compound combining Mg+2 with
Cl-1?
8. When combining oppositely charged ions that contain polyatomic ions, where does the subscript go?
9. When naming binary ionic compounds, which ion is placed first? metal/positive or nonmetal/negative (circle one)
Which is placed last? metal/positive or nonmetal/negative (circle one)
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10. When naming ionic compounds, does the name of the first ion (element) change?
11. When naming ionic compounds, how does the name of the anion change?
12. How would you correctly name the following compounds:
KCl _________________________________
MgS ________________________________
AlN _________________________________
13. Does the name found on reference table E ever change?
14. Correctly name the following ionic compounds containing polyatomic ions?
NH4Cl ______________________________________
NH4NO3 ____________________________________
15. Explain how to name a compound that used Fe+2 versus a compound that used Fe+3 (using the stock system):
16. Complete the following table indicating the Roman numeral that matches with the correct ionic charge:
Roman Numeral
I
II
III
Iv
V
VI
VII
(+) charge on transition metal
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Writing Binary Ionic Formulas:
- goal is to combine cations & anions to get a net zero charge
- use subscripts to show how many of each ion you need
** empirical formula shows the lowest whole number ratio of ions or elements in a compound
- “criss-cross” rule
1) write the cation & anion with charge as superscripts
2) criss-cross the charges to become subscripts
3) reduce subscripts to a lowest whole number ratio
ex. Potassium oxide
ex. Zinc phoshide
Polyatomic Ions: Ion composed of more than one element covalently bonded together. Located on
reference table E
They are written in parentheses ( ) with the net charge outside as a superscript. Treat them as ONE UNIT!
When writing formulas, copy the polyatomic ion as it is written on ref. table E , put ( ) around it and the
charge as a superscript. After you use the criss-cross rule, place the subscript OUTSIDE the ( ) !!!
ex. Sodium carbonate
ex. Strontium thiocyanate
Naming Ionic Compounds:
 cation named first -> use element name or cation name
 Stock System – the roman numeral = charge on metal
**use the metal’s name followed by the roman numeral that is equal to the charge
** the suffix “-ous” denotes the lower oxidation state
** the suffix “-ic” denotes the higher oxidation state
ex. iron(II) = Fe+2 = ferrous
iron(III) = Fe+3 = ferric
 anion named second
 if monatomic (from periodic table) change ending to “-ide”
 if polyatomic (from ref. Table E) use name directly
***be sure to place the polyatomic ion in parenthesis,with the subscript outside the ( ) !!!!!
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WRITING BINARY & POLYATOMIC FORMULAS
Directions: write the balanced formula and the correct name for the ionic compounds, resulting from the
following combinations of ions, on the lines provided. Determine the correct ions when required.
IONS
1
Mg+2 & S-2
2
K+ & NO3-2
3
Mg+2 & CO3-2
4
Fe+3 & O-2
5
Na+ & F-
6
Ba+1 & SO4-2
7
Cu+2 & Br-1
8
Na+1 & SO4-2
9
Mg+2 & SO4-2
10
NH4+1 & CO3-2
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Al+3 & (OH)-1
12
Pb+2 & NO3-1
13
Al+3 & SeO4-1
14
Sr+2 & CO3-2
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FORMULA
NAME
Ca(ClO4)2
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ammonium acetate
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dimercury oxide
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NH4CH3COO
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Ni3(PO4)2
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hydrogen phosphate
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22
(NH4)3PO4
Ag+1 & NO3-1
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Name ________________________________________
Date__________________________
Use Review Book Pages 27-32, 104-106
Period_________________________
1. Define and give an example of a DIATOMIC MOLECULE:
2. Which elements exist in nature as diatomic molecules?
3. Covalently bonded substances form discrete units called ________________________________.
4. Explain the difference between an empirical formula and a molecular formula. Provide an example using carbon,
hydrogen, and oxygen.
5. Which element is written first in the formula of a binary covalent molecule? (p32)
6. Complete the following table indicating the common prefixes for the number of atoms:
Number of atoms
1
2
3
4
5
6
7
8
Prefix
7. Correctly name the following binary covalent compounds:
CO ___________________________________
CO2 _____________________________
NO _____________________________________
N2O4 ________________________________
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Proceed to topic 6 (p. 104) to complete the following:
8. Chemical bonds occur when the attractive forces are greater than the _____________________________
________________________________________________________________________________________.
9. Covalent bonds occur when 2 nuclei _________________________ electrons in order to achieve a stable
arrangement of electrons. They are often formed between 2 _____________________ atoms.
10. Complete the following graphic organizer comparing polar and nonpolar bonds:
COVALENT BONDS
Involve ____________________electrons between 2 of
the same or different ________________________ atoms
NONPOLAR COVALENT
POLAR COVALENT
Attraction of 2 nuclei is _________________,
causing the electrons to be shared
__________________. Electronegativity values
are ___________________ or _____________
in value.
Electronegativity values are _______________
in value. Attraction of 2 nuclei is
_________________, causing the electrons to
be shared __________________.
The element with the higher electronegativity
value will attract the shared electrons
more/less (circle one), causing a partial
____________________ charge
11. Oxygen (O2) shares ________ pair of electrons between the 2 oxygen atoms, resulting in a ______________
covalent bond.
12. Nitrogen (N2) shares ________ pair of electrons between the 2 oxygen atoms, resulting in a _______________
covalent bond.
13. Molecular substances tend to exist as ___________________, __________________, and __________ depending
on strength of attractions.
14. Molecular substances tend to be hard/soft (circle one), be poor/good (circle one) conductors of heat and electricity,
and have relatively low/high (circle one) melting and boiling points.
15. List five (5) examples of molecular substances:
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Name: ______________________________________ Partner: ________________________________
IONIC & COVALENT BONDING REINFORCEMENT
Directions: Use the word banks provided (some terms may be used more than once or not at all), your note
packet and review book to complete the following.
Sharing
Metal
Octet Attractive
Positively
Greater than One
Transfer
Nonmetal
Loss
Electrostatic
Neutrally
Equal to
Eight
Accepting
Metalliod
Gain
Chemical
Negatively
Less than
Zero
1. An ionic bond is formed when ions bond together because of __________________________
attraction of the oppositely charged ions. Ionic bonds result from the _________________ of
electrons from the ____________________ charged ion to the ________________________
charged ion. The ions form bonds in order to satisfy the ______________________ rule, having
______________ valence electrons. To predict if a formula is an ionic solid the electronegativity
difference would be ________________________________1.7, usually between ____________
and ______________, which are found far apart/close together (circle one) on the periodic table.
2. A covalent bond is formed when nuclei ___________________ electrons in order to satisfy the
______________________ rule, having ______________ valence electrons. To predict if a formula
is an ionic solid the electronegativity difference would be
________________________________1.7, usually between two _____________________, which
are found far apart/close together (circle one) on the periodic table.
3. Label the following number line, representing the EN, with the following terms:
Ionic Bond
Polar Covalent Bond
Nonpolar Covalent Bond
2 same nonmetal
2 different nonmetal
metal & nonmetal
equal sharing of electrons
unequal sharing of electrons
transfer of electrons
4. Use your flowchart and reference tables to complete the following table:
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Lewis Dot
of Ionic Solid
Ions
1.
Li+1 & F-1
2.
Al+3 & Br-1
3.
Ba+2 & (OH)-1
4.
Cu+1 & (CO3)-2
5.
Fe+3 & (PO4)-3
Balanced
Formula
Name
5. Use your note packet, “bonding activity flashcards” and review book to complete the table:
Name
1.
Chlorine
2.
Oxygen
3.
Nitrogen
4.
Hydrogen
Chloride
5.
6.
7.
8.
Molecular
Formula
Structural
(Lewis dot)
Formula
Ball and Stick
Model
Bond
Type
(PC/NPC)
Molecular
Polarity
Molecular
Shape
Water
Ammonia
Carbon
Tetrachloride
Carbon
Dioxide
C-H:
7.
Methyl
Flouride
CH3F
C-F:
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6. Complete the following table, comparing and contrasting the properties of ionic solids and covalent
molecules
Characteristic
Ionic Solids
Covalent Molecules
Mode of bonding


EN
Location on periodic table
Type of elements
Hard or soft
Melting point
Example substances
7. Answer the following review book questions, place you answers neatly in the space provided:
Pg 99
1
2
3
4
5
Answer:
Pg. 102
7
9
Answer:
Pg. 105
Answer:
Pg. 107
Answer:
Pg. 110
Answer:
13
18
14
19
20
15
21
16
22
17
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
Answer:
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Name ________________________________________
Date__________________________
Use Review Book Pages 100, 106-113
Period_________________________
1. Complete the following chart depicting the types of formulas (p 106):
Molecular
Structural
Ball and Stick
Name
Formula
Formula
Model
Space Filling
Model
Lewis Dot
Diagram (p100)
Hydrogen
Water
Ammonia
2. According to the “rules’ for drawing Lewis diagrams for compounds, which element is generally written first or
placed in the center? (p100)
3. According to the “rules’ for drawing Lewis diagrams for compounds, which valence electron “dots” are placed next
to each other, forming a bond?
4. How many valence electrons are shared in a single bond? ________________ In a double bond? ______________
In a triple bond? ________________
5. Draw the correct Lewis diagrams for the following:
Cl2
O2
N2
CH3Cl
C2H2
6. Metallic bonds have few/many (circle one) electrons, low/high(circle one) ionization energies, and low/high(circle one)
melting and boiling points due to strong bonds. Metallic bonds involve what type of element? __________________
7. Metallic bonds result from the force of attraction of the _______________________________________________
for the atom’s ___________________________________________ kernel.
8. The malleability of metals can be attributed to the freedom of valence electrons, referred to as a “ _____________
_______________________________________________”.
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9. Complete the following table that compares polar and nonpolar molecules, as in figure 6-10:
POLAR MOLECULE
NONPOLAR MOLECULE
Symmetry?
Example
diagrams/substances
Distribution of charge?
10. Compare the properties of metallic, ionic and covalent bonds:
Bond
Type
Melting & Boiling Points
Hardness
Conduct as Solid?
Conduct as Liquid?
Conduct as Aqueous?
Metallic
Covalent
Ionic
11. Compare the types of INTERMOLECULAR FORCES OF ATTRACTION (IMFs):
Type of IMF
Dipole-Dipole
Hydrogen Bonds
London Dispersion Forces
Description
Example substances
(diagram)
Special Properties
Name: ______________________________________ Partner: ________________________________
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BOND TYPE REINFORCEMENT
Directions: Use your note packet and review book (pp 102 & 110) to complete the following:
1. Metallic bonds form between atoms of ___________________(type of element). They form because
atoms of metals have HI/LO
(circle one)
ionization energies and MANY/FEW (circle one) valence
electrons. Metallic bonds are characterized by being __________________, having
______________MP & BP. Exceptions are _____________, which is a liquid at RT, and group
________________ elements. The valence electrons _______________ freely throughout the
crystal and the bond results from the force of ________________ of _____________ valence
electrons for an atom’s _______________ charged kernel. The term used to describe metallic
bonding is “_______________________________”. Metallic bonds are good conductors of heat and
electricity in the _____________ and _____________ phase or in ______________ solutions. Ionic
solids are poor/good conductors (circle one) in the solid phase, but become conductors when
fused/melted in the __________ state or dissolved in ________________ ________________.
Molecular substances are held by _________________ bonds and are always poor/good(circle one)
conductors.
2. Complete the following table distinguishing between bond type properties:
Bond Type
MP & BP
Hardness
Representative
Aqueous
Compound or
Solid
Liquid
soln.
Element
Conductivity Conductivity Conductivity
METALLIC
COVALENT
IONIC
3. Answer the following questions from the review book:
Pg 103
10
Answer:
Pg 111
Answer:
38
39
40
11
41
12
42
43
44
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Name: _______________________________________ Date: ______________________ Section: ___________
?
Answer the following on the lines provided. Be sure to address the “in terms of” questions appropriately.
1.) Why do we calculate EN?______________________________________________________________
____________________________________________________________________________________
2.) Why do we look at the symmetry or charge distribution of a molecular structure? _________________
____________________________________________________________________________________
3.) Why do we need to know how to determine the number of valence electrons,
a. In terms of drawing a Lewis structure?_________________________________________________
________________________________________________________________________________
b. In terms of bond type? _____________________________________________________________
________________________________________________________________________________
c. In terms of an element’s location on the periodic table? __________________________________
________________________________________________________________________________
d. In terms of chemical reactivity?_______________________________________________________
________________________________________________________________________________
e. In terms of ion formation?___________________________________________________________
________________________________________________________________________________
4.) Why do we need to know how much energy is released in forming a bond, in terms of stability of the
compound formed? ___________________________________________________________________
____________________________________________________________________________________
5.) Why do chemists use the stock system when naming ionic substances? Give an example. ___________
______________________________________________________________________________________
__________________________________________________________________________________
6.) Why do we use subscripts in ionic formulas, in terms of the octet rule? __________________________
____________________________________________________________________________________
7.) Why are salt (NaCl) and sugar (C6H12O6) representative compounds in the bonding unit, in terms of
properties of substances? ______________________________________________________________
_______________________________________________________________________________________________
___________
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Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
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Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
Definition
Characteristics
Examples
Non-examples
Pictures/Diagrams
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Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
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Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
Definition
Examples
Characteristics
Non-examples
Pictures/Diagrams
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