CHEM 219 MODULE 1 PROBLEM SET Questions with Correct Solutions
Question:
1. On a piece of scratch paper, write out the Lewis Dot Diagram for each of the indicated
elements and determine the following for each:
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. Oxygen Carbon Hydrogen Nitrogen
Answer:
Oxygen - a) 2 b) 2 c) 2 Carbon - a) 0 b) 4 c) 4 Hydrogen- a) 0 b) 1 c) 1 Nitrogen - a) 1 b) 3 c) 3
Question:
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
b. K and Cl
c. P and Cl
d. C and O
e. Na and Br
Answer:
a. Br-Br: Electronegativity difference () = 0 = COVALENT (or pure covalent)
b. K-Cl: () = 2.2 = IONIC
c. P-Cl: ()= 0.9 = POLAR COVA- LENT
d. C-O: ()= 1.0 = POLAR COVA- LENT
e. Na-Br: () = 1.8 = POLAR CO- VALENT
Question:
3. Define the term constitutional isomer.
Answer:
Two (or more) different chemical compounds with the same molecular formula but different
connectivity between the atoms in their structural formulae.
Question:
4. Explain (using specific evidence) what makes the following two compounds constitutional
isomers of one another:
Answer:
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.
, Question:
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.
Answer:
Different compounds that are not related. They have different MF - (a) C3H8O, (b) C3H6O.
Question:
6. Identify each of the following carbon skeletons as linear (continuous), branched, or cyclic.
Answer:
a) Branched
b) Linear (continuous)
c) Cyclic
Question:
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:
4
Question:
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
Question:
9. Write the molecular formula for each of the compounds whose bond-line formulae are
given below.
Question:
1. On a piece of scratch paper, write out the Lewis Dot Diagram for each of the indicated
elements and determine the following for each:
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. Oxygen Carbon Hydrogen Nitrogen
Answer:
Oxygen - a) 2 b) 2 c) 2 Carbon - a) 0 b) 4 c) 4 Hydrogen- a) 0 b) 1 c) 1 Nitrogen - a) 1 b) 3 c) 3
Question:
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
b. K and Cl
c. P and Cl
d. C and O
e. Na and Br
Answer:
a. Br-Br: Electronegativity difference () = 0 = COVALENT (or pure covalent)
b. K-Cl: () = 2.2 = IONIC
c. P-Cl: ()= 0.9 = POLAR COVA- LENT
d. C-O: ()= 1.0 = POLAR COVA- LENT
e. Na-Br: () = 1.8 = POLAR CO- VALENT
Question:
3. Define the term constitutional isomer.
Answer:
Two (or more) different chemical compounds with the same molecular formula but different
connectivity between the atoms in their structural formulae.
Question:
4. Explain (using specific evidence) what makes the following two compounds constitutional
isomers of one another:
Answer:
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.
, Question:
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.
Answer:
Different compounds that are not related. They have different MF - (a) C3H8O, (b) C3H6O.
Question:
6. Identify each of the following carbon skeletons as linear (continuous), branched, or cyclic.
Answer:
a) Branched
b) Linear (continuous)
c) Cyclic
Question:
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:
4
Question:
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
Question:
9. Write the molecular formula for each of the compounds whose bond-line formulae are
given below.
