Chem 1211 Exam 4 questions well
answered rated A+
Resonance Structure - correct answer ✔✔Multiple Lewis structure for a molecule that differ
only by electron position
Resonance Hybrid - correct answer ✔✔Molecule is a combination of the resonance forms
-Molecule does not resonate between the two forms
Look for multiple bonds or lone pairs - correct answer ✔✔O3
Resonance structures must have (part 1 of 4) - correct answer ✔✔1. Same connectivity
between atoms
• only electron positions can change
Resonance structures must have (part 2 of 4) - correct answer ✔✔2. Same number of electrons
• Bonding and nonbonding
Resonance structures must have (part 3 of 4) - correct answer ✔✔-Second row elements have a
maximum of 8 electrons
• Third row can have expanded octets (d-orbitals)
Resonance structures must have (part 4 of 4) - correct answer ✔✔3.Same overall formal charge
• Better structures = fewer and smaller formal charges
• Better structures = formal charge on more electronegative atom
,Drawing Resonance Structures (part 1 of 3) - correct answer ✔✔1. Draw Lewis structure that
maximizes octets
2. Assign formal charges
Drawing Resonance Structures (part 2 of 3) - correct answer ✔✔3. Move electron pairs from
atoms with (-) FC toward atoms with (+) FC
4. If (+) FC atom 2nd row, only move in electrons if you can move out electron pairs from
multiple bond
Drawing Resonance Structures (part 3 of 3) - correct answer ✔✔5. If (+) FC atom 3rd row or
below, keep bringing in electron pairs to reduce the FC, even if get expanded octet.
Covalent bonding between different atoms results in - correct answer ✔✔in unequal sharing of
electrons
Bond Polarity - correct answer ✔✔The more electronegative atom has a greater electron
density
- Result is a polar covalent bond
Greater difference in electronegativity - correct answer ✔✔more polar bond
Pure (nonpolar) covalent bond - correct answer ✔✔electrons shared equally (0-0.4)
Polar covalent bond - correct answer ✔✔electrons shared unequally (0.4-2.0)
ionic bond - correct answer ✔✔electrons transferred (2.0-4.0)
Bond Dipole Moment - correct answer ✔✔Quantitative way of describing the polarity of a bond
, Describing Polarity of a bond - correct answer ✔✔positively- and negatively-charged ends
- measured value
Directly proportional to - correct answer ✔✔magnitude of partial charges and distance
between charges
Measuring Bond polarity - correct answer ✔✔- μ = (q)(r)
- Measured in Debeyes (D)
VSEPR - correct answer ✔✔Valance Shell electron pair repulsion theory
Electron Groups - correct answer ✔✔-Repel one another
•around the central atom will be most stable when they areas far apart as possible
Electron groups on the central atom include: - correct answer ✔✔- Lone pairs (non-bonding
electrons)
- Bonding atoms
Linear Geometry - correct answer ✔✔-number of e on central atom = 2
-molecular and electron geometry = linear
-bond angles = 180
Linear Geometry Picture - correct answer ✔✔
Trigonal Planar Geometry - correct answer ✔✔- number of e on central atom = 3
- molecular geometry = trigonal planar
answered rated A+
Resonance Structure - correct answer ✔✔Multiple Lewis structure for a molecule that differ
only by electron position
Resonance Hybrid - correct answer ✔✔Molecule is a combination of the resonance forms
-Molecule does not resonate between the two forms
Look for multiple bonds or lone pairs - correct answer ✔✔O3
Resonance structures must have (part 1 of 4) - correct answer ✔✔1. Same connectivity
between atoms
• only electron positions can change
Resonance structures must have (part 2 of 4) - correct answer ✔✔2. Same number of electrons
• Bonding and nonbonding
Resonance structures must have (part 3 of 4) - correct answer ✔✔-Second row elements have a
maximum of 8 electrons
• Third row can have expanded octets (d-orbitals)
Resonance structures must have (part 4 of 4) - correct answer ✔✔3.Same overall formal charge
• Better structures = fewer and smaller formal charges
• Better structures = formal charge on more electronegative atom
,Drawing Resonance Structures (part 1 of 3) - correct answer ✔✔1. Draw Lewis structure that
maximizes octets
2. Assign formal charges
Drawing Resonance Structures (part 2 of 3) - correct answer ✔✔3. Move electron pairs from
atoms with (-) FC toward atoms with (+) FC
4. If (+) FC atom 2nd row, only move in electrons if you can move out electron pairs from
multiple bond
Drawing Resonance Structures (part 3 of 3) - correct answer ✔✔5. If (+) FC atom 3rd row or
below, keep bringing in electron pairs to reduce the FC, even if get expanded octet.
Covalent bonding between different atoms results in - correct answer ✔✔in unequal sharing of
electrons
Bond Polarity - correct answer ✔✔The more electronegative atom has a greater electron
density
- Result is a polar covalent bond
Greater difference in electronegativity - correct answer ✔✔more polar bond
Pure (nonpolar) covalent bond - correct answer ✔✔electrons shared equally (0-0.4)
Polar covalent bond - correct answer ✔✔electrons shared unequally (0.4-2.0)
ionic bond - correct answer ✔✔electrons transferred (2.0-4.0)
Bond Dipole Moment - correct answer ✔✔Quantitative way of describing the polarity of a bond
, Describing Polarity of a bond - correct answer ✔✔positively- and negatively-charged ends
- measured value
Directly proportional to - correct answer ✔✔magnitude of partial charges and distance
between charges
Measuring Bond polarity - correct answer ✔✔- μ = (q)(r)
- Measured in Debeyes (D)
VSEPR - correct answer ✔✔Valance Shell electron pair repulsion theory
Electron Groups - correct answer ✔✔-Repel one another
•around the central atom will be most stable when they areas far apart as possible
Electron groups on the central atom include: - correct answer ✔✔- Lone pairs (non-bonding
electrons)
- Bonding atoms
Linear Geometry - correct answer ✔✔-number of e on central atom = 2
-molecular and electron geometry = linear
-bond angles = 180
Linear Geometry Picture - correct answer ✔✔
Trigonal Planar Geometry - correct answer ✔✔- number of e on central atom = 3
- molecular geometry = trigonal planar
