Module 1 Problem Set: ANSWERS IN RED
1. To help yourself, write out the Lewis Dot Diagram for each of the indicated elements
on a piece of scratch paper; determine the following for each and fill in the chart
with your answers:
A. The number of Lone Pairs the atom possesses in its valence shell.
B. The number of Unpaired Electrons the atom possesses in its valence shell.
C. The number of bonds the atom will form.
ANSWER:
1. Oxygen: A) 2 B) 2 C)2
2. Carbon: A) 0 B) 4 C) 4
3. Hydrogen: A) 0 B)1 C) 1
4. Nitrogen: A) 1 B) 3 C) 3
2. Classify the bonding between the given pairs of atoms as ionic, covalent, or polar
covalent. Use the table of electronegativities shown below to help with the classification.
a. Br and Br = covalent
b. K and Cl = Ionic
c. P and Cl = Polar Covalent
d. C and O = Polar Covalent
e. Na and Br = Polar Covalent
,3. Define the term constitutional isomer.
CHANGE WORDING Answer:
Two (or more) different chemical compounds with the same molecular formula but different
connectivity between the atoms in their structural formulae.
4. Explain (using specific evidence) what makes the following two compounds
constitutional isomers of one another:
Both compounds have a MF of C3H6O – same MF.
Compound “a” has a 3-carbon chain with a C=O in the middle. No H atom connected to C
of C=O.
Compound “b” has a 3-carbon chain with a C=O at the end. There is an H attached to the
C of the C=O.
5. What is the relationship between the compounds shown? Are they the same compound,
constitutional isomers, or two different compounds that are not related to one another? Explain.
Different compounds that are not related. They have different MF – (a) C3H8O, (b)
C3H6O.
6. Identify each of the following carbon skeletons as linear (continuous), branched, or
cyclic.
,a) Branched
b) Linear (continuous)
c) Cyclic
7. On a piece of scratch paper, write out structural formulae for all of the constitutional isomers
possible for the MF C3H6F2. How many isomers are possible for this formula?
Answer:
FOUR (shown below)
8. Characterize each of the following structural formula representations as either a dash,
condensed, super-condensed, or bond-line formula:
Answer:
a) Super-Condensed
b) Condensed
c) Bond-line
d) Dash
, 9. Write the molecular formula for each of the compounds whose bond-line formulae are
given below.
Answer:
a) C5H10
b) C3H8O
c) C4H10O
10. Which bond-line formula shown below represents a constitutional isomer of
CH3CH2CH2CH2CH3?
Answer:
(b)
11. Which of the following structures does NOT have the molecular formula C6H14?
Answer D
12. The structural formula:
1. To help yourself, write out the Lewis Dot Diagram for each of the indicated elements
on a piece of scratch paper; determine the following for each and fill in the chart
with your answers:
A. The number of Lone Pairs the atom possesses in its valence shell.
B. The number of Unpaired Electrons the atom possesses in its valence shell.
C. The number of bonds the atom will form.
ANSWER:
1. Oxygen: A) 2 B) 2 C)2
2. Carbon: A) 0 B) 4 C) 4
3. Hydrogen: A) 0 B)1 C) 1
4. Nitrogen: A) 1 B) 3 C) 3
2. Classify the bonding between the given pairs of atoms as ionic, covalent, or polar
covalent. Use the table of electronegativities shown below to help with the classification.
a. Br and Br = covalent
b. K and Cl = Ionic
c. P and Cl = Polar Covalent
d. C and O = Polar Covalent
e. Na and Br = Polar Covalent
,3. Define the term constitutional isomer.
CHANGE WORDING Answer:
Two (or more) different chemical compounds with the same molecular formula but different
connectivity between the atoms in their structural formulae.
4. Explain (using specific evidence) what makes the following two compounds
constitutional isomers of one another:
Both compounds have a MF of C3H6O – same MF.
Compound “a” has a 3-carbon chain with a C=O in the middle. No H atom connected to C
of C=O.
Compound “b” has a 3-carbon chain with a C=O at the end. There is an H attached to the
C of the C=O.
5. What is the relationship between the compounds shown? Are they the same compound,
constitutional isomers, or two different compounds that are not related to one another? Explain.
Different compounds that are not related. They have different MF – (a) C3H8O, (b)
C3H6O.
6. Identify each of the following carbon skeletons as linear (continuous), branched, or
cyclic.
,a) Branched
b) Linear (continuous)
c) Cyclic
7. On a piece of scratch paper, write out structural formulae for all of the constitutional isomers
possible for the MF C3H6F2. How many isomers are possible for this formula?
Answer:
FOUR (shown below)
8. Characterize each of the following structural formula representations as either a dash,
condensed, super-condensed, or bond-line formula:
Answer:
a) Super-Condensed
b) Condensed
c) Bond-line
d) Dash
, 9. Write the molecular formula for each of the compounds whose bond-line formulae are
given below.
Answer:
a) C5H10
b) C3H8O
c) C4H10O
10. Which bond-line formula shown below represents a constitutional isomer of
CH3CH2CH2CH2CH3?
Answer:
(b)
11. Which of the following structures does NOT have the molecular formula C6H14?
Answer D
12. The structural formula:
