CHEM 219 Module 1 problem set
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 - answerOxygen - 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
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 - answera. Br-Br: Electronegativity difference () = 0 = COVALENT (or pure
covalent)
b. K-Cl: () = 2.2 = IONIC
c. P-Cl: ()= 0.9 = POLAR COVALENT
d. C-O: ()= 1.0 = POLAR COVALENT
e. Na-Br: () = 1.8 = POLAR COVALENT
Define the term constitutional isomer. - answerTwo (or more) different chemical
compounds with the same molecular formula but different connectivity between the
atoms in their structural formulae.
Explain (using specific evidence) what makes the following two compounds
constitutional isomers of one another: - answerBoth 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.
, 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. - answerDifferent compounds that are not related. They have different MF - (a)
C3H8O, (b) C3H6O.
Identify each of the following carbon skeletons as linear (continuous), branched, or
cyclic. - answera) Branched
b) Linear (continuous)
c) Cyclic
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?
- answer4
Characterize each of the following structural formula representations as either a dash,
condensed, super-condensed, or bond-line formula: - answera) Super-Condensed
b) Condensed
c) Bond-line
d) Dash
Write the molecular formula for each of the compounds whose bond-line formulae are
given below. - answera) C5H10
b) C3H8O
c) C4H10O
Which bond-line formula shown below represents a constitutional isomer of
CH3CH2CH2CH2CH3? - answer(b)
Which of the following structures does NOT have the molecular formula C6H14? -
answer(d)
The structural formula:
Has what molecular formula? - answer(c) C7H14
The compound carbon monoxide has the following structural formula:
What is the formal charge on the carbon and the oxygen? Show your calculation. What
is the overall charge on the molecule? - answerCarbon = 4-(2+3) = -1
Oxygen = 6-(2+3) = +1
Overall = FC Carbon + FC Oxygen = [-1 + (+1)] = 0
For the following example of resonance:
Which structure (a or b) represents a "major" resonance contributor to the hybrid?
Briefly explain why. - answerStructure "a" is a major contributor. All of the atoms have
complete valences and in addition, all of the atoms have a formal charge of zero (All of
the atoms are meeting their LDD bonding pattern).
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 - answerOxygen - 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
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 - answera. Br-Br: Electronegativity difference () = 0 = COVALENT (or pure
covalent)
b. K-Cl: () = 2.2 = IONIC
c. P-Cl: ()= 0.9 = POLAR COVALENT
d. C-O: ()= 1.0 = POLAR COVALENT
e. Na-Br: () = 1.8 = POLAR COVALENT
Define the term constitutional isomer. - answerTwo (or more) different chemical
compounds with the same molecular formula but different connectivity between the
atoms in their structural formulae.
Explain (using specific evidence) what makes the following two compounds
constitutional isomers of one another: - answerBoth 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.
, 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. - answerDifferent compounds that are not related. They have different MF - (a)
C3H8O, (b) C3H6O.
Identify each of the following carbon skeletons as linear (continuous), branched, or
cyclic. - answera) Branched
b) Linear (continuous)
c) Cyclic
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?
- answer4
Characterize each of the following structural formula representations as either a dash,
condensed, super-condensed, or bond-line formula: - answera) Super-Condensed
b) Condensed
c) Bond-line
d) Dash
Write the molecular formula for each of the compounds whose bond-line formulae are
given below. - answera) C5H10
b) C3H8O
c) C4H10O
Which bond-line formula shown below represents a constitutional isomer of
CH3CH2CH2CH2CH3? - answer(b)
Which of the following structures does NOT have the molecular formula C6H14? -
answer(d)
The structural formula:
Has what molecular formula? - answer(c) C7H14
The compound carbon monoxide has the following structural formula:
What is the formal charge on the carbon and the oxygen? Show your calculation. What
is the overall charge on the molecule? - answerCarbon = 4-(2+3) = -1
Oxygen = 6-(2+3) = +1
Overall = FC Carbon + FC Oxygen = [-1 + (+1)] = 0
For the following example of resonance:
Which structure (a or b) represents a "major" resonance contributor to the hybrid?
Briefly explain why. - answerStructure "a" is a major contributor. All of the atoms have
complete valences and in addition, all of the atoms have a formal charge of zero (All of
the atoms are meeting their LDD bonding pattern).
