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Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
Monatomic
1. Elements that exist as single atoms are called _______.
Molecules
2. Are neutral groups of atoms joined together by covalent bonds
Covalent bond
3. Is formed when two atoms share electrons
Sharing electrons
4. This takes place between neutral atoms with covalent compounds
Attractive
5. In order for a bond to form __________ and ________ forces must be _________
Repulsive
Equal
Diatomic molecules 6. Molecules consisting of two atoms
HI BrONClF
7. Mnemonic device used to remember diatomic molecules
Hydrogen
8. The seven diatomic molecules
Iodine
Bromine
Oxygen
Nitrogen
Chlorine
Fluorine
Molecular compounds
9. Are composed of molecules
Same
10. The molecules of a given molecular compound are all the ______
Low
11. Molecular compounds tend to have relatively ______ melting & boiling points
Liquids
12. Most molecular compounds are _____ or ________ at room temperature
Gases
Nonmetals
13. Most molecular compounds are composed of atoms of two or more ________
Molecular compounds
Molecular formula
14. Also known as covalent compounds
15. Is the chemical formula of a molecular compound
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
How many
16. A molecular formula shows _______ atoms of each element are present
Arrangement
17. Molecular formula does NOT tell you the __________of the atoms in the molecule
Noble gases
18. Covalent bonds occur so that atoms attain the electron configurations of __________
4A
19. These groups are most likely to form covalent bonds
5A
6A
7A
Single covalent bond
Hydrogen
20. Forms as a result of two atoms sharing one pair of electrons
21. These diatomic molecules prefer to form single covalent bonds
Chlorine
Fluorine
Bromine
Iodine
A dash
22. A single covalent bond can be represented by a ________ or a _________
An electron dot structure
Structural formulas 23. These represent covalent bonds by dashes and show the arrangement of covalently
bonded atoms
Unshared pair
24. Is a pair of valence electrons that are not shared between atoms
Double
25. Atoms can form ________ or __________ bonds by sharing two or three pairs of
electrons
Triple
Double covalent bond
26. Sharing two pairs of electrons results in a _______________
Triple covalent bond
27. Sharing three pairs of electrons results in a __________________
Oxygen
28. These two atoms prefer to form double bonds
Sulfur or carbon
Lone pair
29. An unshared pair is also called a ____________________
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
Nitrogen
30. This atom prefers to form a triple bond
Hydrogen
31. ________ and _______ atoms like to be at the ends of molecules
Halogen
Carbon
32. This atom prefers the center of molecules
Lowest electronegativity
Hydrogen
33. When carbon is not involved in a molecule, then the atom with the
___________ is placed in the center
34. These atoms are exceptions to the octet rule when bonding
Beryllium
Boron
Sulfur (sometimes)
Phosphorus (sometimes)
Coordinate
35. This is a covalent bond in which one atom contributes both bonding electrons
Carbon monoxide
36. Example of a molecule that forms a coordinate covalent bond
Polyatomic ions
37. Is a group of 2 or more atoms joined by covalent bonds that have a positive or
negative charge and behave as a unit
Covalent bonds
38. Most polyatomic cations and anions contain both _____ and _______ bonds
Coordinate covalent bonds
Ionic
39. Compounds containing polyatomic ions include both _____ and ____ bonding
Covalent
Bond dissociation energy
40. The energy required to break a bond between two covalently bonded atoms
Resonance structures
41. Two or more possible configurations for the same compound that differ in the
arrangement of electrons
ozone
42. An example of a compound that has resonance structures
odd number
43. Octet rule cannot be satisfied in molecules whose total number of valence electrons
is an _____________
kJ/mol
44. Bond energy is measured in ________
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
Fewer
45. There are molecules in which an atom has ______ or ________ than a complete
octet
More
Molecular orbitals
46. This form when two atoms combine and their atomic orbitals overlap
Atomic orbital
47. A molecular orbital is the ______ in which shared electrons move between the ____
of two atoms
Nuclei
Whole
48. A molecular orbital belongs to a molecule as a ____________
Bonding orbital
49. When a molecular orbital becomes occupied by 2 electrons of a covalent bond it is
called a ___________
Sigma bond
50. This forms when two atomic orbitals combine to form a molecular orbital that is
symmetrical around the axis connecting two atomic nuclei
σ
51. Symbol for a sigma bond
Imbalance
52. Covalent bonding results from an ______ between the ______ and ______ of the
nuclei and electrons involved
Attractions
Repulsions
Nuclei
53.
_____ repel other nuclei and ______ repel other electrons due to like charges
Electrons
p
54. Atomic ___ orbitals can also overlap to form molecular orbitals
pi molecular orbital 55. The side-by-side overlap of atomic p orbitals produces a ____________
pi bond
56. When a pi molecular orbital is filled with 2 electrons and bonds it forms a _______
π
57. Symbol of a pi bond
physical
58. Three-dimensional shape is important in determining a molecule’s _______ and
_____ properties
chemical
Linear
59. A molecule made of only 2 atoms has a _______ shape
VSEPR
60. The shape of molecules with more than 2 atoms is determined by a model based on
the _________ theory
109.5°
61. The measure of the tetrahedral angle
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
Unshared
62. _________ pairs of electrons are important in predicting the shapes of molecules
Central atom
63. An unshared pair of electrons on the _______ has the most influence on the shape of
a molecule
More space
64. In VSEPR theory, unshared pairs of electrons occupy ________ around the central
atom than shared pairs
9
65. Number of possible molecular shapes
VSEPR Theory
66. States that the repulsion between electron pairs causes molecular shapes to adjust so
that the valence-electron pairs stay as far apart as possible
Linear
67. List the 9 possible molecular shapes
Trigonal planar
Bent
Pyramidal
Tetrahedral
Trigonal bipyramidal
Octahedral
Square planar
T-shaped
Electronegativity
68. This is used to predict the type of bond that will form between 2 atoms
Equally
69.
Atoms can share electrons _________ or ________ due to differences in ________
Unequally
Electronegativity values
Nonpolar covalent
70. Type of bond formed when electrons are shared equally
Polar covalent
71. Type of bond formed when electrons are shared unequally
Electronegative
72. The more ________ atom attracts electrons more strongly and gains a slightly _____
Negative charge
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
Less
73. The _______ electronegative atom has a slightly __________
Positive charge
Polar bond
Ionic bond
74. Another name for a polar covalent bond
75. When the difference in electronegativity is greater than or equal 2.0, this type of
bond forms
Difference
76. The greater the _______ between the electronegativity values of two elements joined
by a bond, the greater the ______ of that bond
Polarity
Polarity
77. The greater the ______ of a bond the ________ the bond
Stronger
Partial charges
78.
Having __________ indicates that the ______ of electrons will be closer to the atom
with the greater ___________
79.
Range of charges for partial charges
Shared pair
Electronegativity
0 and +1.6 x 10-19
0 and -1.6 x 10-19
Electronegativity differences
80. The amount of partial charge depends on the _____________ between
elements
Polar molecules
81. Molecules that have positive and negative ends
Dipole
82. Specifically a molecule with a partial positive charge on one end and a partially
negative charge on the other end is called a ________
Oppositely
83.
When polar molecules are placed between _________ charged plates, they tend to
become oriented with respect to the _________ and __________ plates
Positive
Negative
δ+ and δ-
84. Symbol used to indicate partial charges
Intramolecular
85.
Intermolecular forces
Are the forces within one molecule
86.
Are forces between multiple molecules
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
London dispersion forces
87.
3 types of intermolecular forces
Hydrogen bonding
Dipole-Dipole interactions
Nonpolar covalent
88.
3 types of intramolecular forces
Polar covalent
Ionic
Intermolecular attractions
89.
These are weaker than either ionic or covalent bonds but are important in
determining physical properties of molecules
Van der Waals Forces 90. Consists of dipole-dipole interactions, hydrogen bonds, and London dispersion
forces
Dipole-Dipole interactions 91. Type of intermolecular attraction that occurs when polar molecules are attracted to
one another
London dispersion
92.
Are the weakest of all Van der Waals forces
Instantaneous dipoles
93.
London dispersion forces are caused by _______________
Instantaneous dipoles
94.
Formed when electrons moving in a molecule get “off balance”
London dispersion
95.
This type of intermolecular attraction occurs between non-polar molecules
Hydrogen bonds
96.
Are attractive forces in which hydrogen that is covalently bonded to a very
electronegative atom is also weakly bonded to an unshared electron pair of another
electronegative atom
Hydrogen
97.
Hydrogen bonding ALWAYS involves ________
Halogen diatomic
98.
Molecules that are attracted to each other mainly by dispersion forces
Water
99.
A common molecule that displays hydrogen bonding
Network solids
100.
Are solids in which all of the atoms are covalently bonded to each other
Large
101.
Melting a network solid requires a _______ amount of energy because all of the
_______ must be broken throughout the solid
Covalent bonds
Covalent Bonding Unit Study Guide
Chemistry
Short Answer: Use complete sentences.
Name: ___________________________
Due Date: February 18, 2016
102. Compare and contrast ionic and covalent compounds. (8 points)
Ionic compounds are made of ions, are held together by ionic or metallic bonds and are usually composed a
of metal with a nonmetal. They also have a higher difference of electronegativity between their atoms.
Covalent compounds are made of molecules, are held together by covalent bonds, share electrons, and are
composed of 2 or more non-metals. They also have a lower difference of electronegativity between their
atoms.
Both types of compounds result from atoms desiring a full octet.
103. Determine the atoms and their amounts in each molecular formula. (2 point each)
a. H2O2 hydrogen-2 and oxygen-2
b. N2O3 nitrogen-2 and oxygen-3
c. PH3
phosphorus-1 and 3-hydrogen
d. CO
carbon-1 and oxygen-1
e. SF6
sulfur-1 and fluorine-6
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
104. Draw the Lewis structure of each molecule. Note: use only single covalent bonds. SHOW WORK! (2 points
each)
a. H
2
e. CH4
8
H:H or H-H
b. Br
14
f. H2S
8
c. HF
8
g. CH2Cl2
20
d. NH3
8
h. SiH4
8
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
105. Draw the Lewis structures for the following polyatomic ions. SHOW WORK! (2 points each)
a. H3O+
8
b. SO42‒
32
c. NH4+
8
d. PO43‒
32
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
106. Draw the Lewis structures of each molecule. Note: multiple bonds are used. SHOW WORK! (2 points
each)
a. SO3
24
c. HCN
10
d. N2
10
b. N2O
16
e. CO2
16
f. C2H2
10
107. Draw the resonance Lewis structures for each compound. SHOW WORK! (2 points each)
a. O3
18
b. SO2
18
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
108. Draw the Lewis structures for each compound. Note: these compounds are exceptions to the octet rule SHOW
WORK! (2 points each)
a. NO2 (has 2 structures)
17
d. PCl5
40
b. ClO2
19
e. SF6
48
c. BF3
24
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
109. Compare and contrast sigma and pi bonds. (5 points)
Sigma bonds are the overlapping of the 2 s or 2 p atomic orbitals end-to-end. Sigma bonds are stronger
than pi bonds.
Pi bonds are the overlapping of 2 p atomic orbitals side-by-side. They are weaker than sigma bonds.
Both are filled with 2 electrons and formed from the overlapping of atomic orbitals
110. What does VSEPR stand for? (1 point)
Valence shell electron pair repulsion theory
111. Draw the Lewis structure for each molecule and determine its molecular shape. (2 points each)
a. NH2Cl
Trigonal pyramid
d. PF5
Trigonal bipyramidal
b. HI
e. SF6
Linear
c. H2O
Octahedral
f. CO32‒
Bent
Trigonal planar
Covalent Bonding Unit Study Guide
Name: ___________________________
Chemistry
Due Date: February 18, 2016
112. Determine the type of bond that will form between each of the following pairs of atoms. (1 point each)
a. N and H
Polar Covalent
b. F and F
Nonpolar
c. Ca and Cl
Ionic
d. Al and Cl
polar covalent & ionic depending
e. H and Br
Polar covalent
f. K and O
Ionic
g. C and O
Polar covalent
h. Cl and F
Polar covalent