CHM 2046C Module-4iii Homework Packet Name: ____________________Please complete the following homework sections before you attempt the exam. This is homework. You grade it. This completed packet is due the day of the exam. No credit for a section if the sample problem is shown and you leave any additional problems which do not show the answer blank.)

Module Four Part III: Chemical Bonding & Molecular Structure (Chapters 8-9)B1 _____(07) Lewis Dot/Stick Structures via Formal Charge Steric #2-#6 Section 8.7 AnswersL1. ____ (01) Bond Angles/Bond Lengths Steric #5&6-Section 9.2 AnswersM._____ (00) Molecular Orbitals Section 9.7-9.8N1. ____ (01) Geometry of Molecules-Steric #5&6 Section 9.1-9.2 Answers O1. ____ (01) Polarity of Molecules- Steric #5&6 Section 8.6, 9.3 Answers P1. ____ (01) Hybrid Orbital Recognition Steric #5&6-Sect 9.5-6 AnswersP2._____(00) Valence Bond Theory Section 9.4Q. _____ (01) Formal Charge-Section 8.7 page 377-384 AnswersR. _____ (01) Resonance Structures Section 8.8 AnswersS. _____ (01) Sigma/Pi Bonding Section 9.6 Answers______(14) Total

Module Four III: Part B1 Dot Structures of Molecules Review 7 pointsUsing a periodic chart draw the electron dot/stick structures of the following molecules. Use the method of formal charges to show the best structure: (Steric Numbers 2-6)

H2SO4 Also look at: H2SO3 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

H3PO4 Also look at: H3PO3

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

HClO4 Also Look at: HClO3 HClO2 HClO FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SO2 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SO3 Formal = Valence - Nonbonding - Bonding e 1- = Total

Charge Electrons Val Electrons 2

SF6 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SF4 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SbCl5 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

PCl5 Also look at PCl3 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

AsF5 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SeF6 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

HArF (first Nobel Gas Molecule) FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

Br21-

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

XeF4 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

XeO4

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

BrCl3 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

PCl61-

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

BrF41+

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

SO2Cl2 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

KrF2 FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total

Other Ions/Compounds to consider which may be the exam question: ClF5 AsF6

1- SeF4 PF3Cl2 I31- BrF5

Reading Reference: Sections 8.5 Octet Rule and 8.7 Formal Charge (page 374)Reference Octet Rule: B. Dot Structures of Covalent Compounds Section 2.10, 6.6, 7.1, 7.5, 7.6 Octet Rule Answers: http://www.fccj.us/chm2045/SampleTest/45M4bAnswers.htm

Module Four: Part L1 Bond Angles 1 pointSteric Numbers #2--#6. What is the bond Angle in the following structures:

______1. Bond Angle between O=S=O in Sulfur dioxide

______2. Bond Angle between any O = S = O in Sulfur trioxide

______3. Bond Angle between any F – Br – F in Bromine Trifluoride

______4. Bond Angle between any O = Xe = O in Xexon Tetroxide

_____5. Bond Angle between either O = S – O in Sulfuric Acid

_____6. Bond Angle Between either O = P – O in Phosphoric Acid

_____7. Bond Angle Between either O = Cl = O in Perchloric Acid

_____8. Bond Angle between any F – Xe – F in Xexon Tetrafluoride

____10. Bond Angle between any equatorial F – Br – F in Bromine Pentafluoride

____11. Bond Angle between axial F – Br and any equatorial F-B in Bromine Pentafluoride

____12. Bond Angle between any equatorial F – As – F in Arsenic Pentafluoride

____13. Bond Angle between either axial F – As and any equatorial F- As in Arsenic Pentafluoride

____14. Bond angle between axial F – As and the other axial F – As in Arsenic pentafluoride

Reading Reference: Jespersen 7th Section 9.2; Note Figurer 9.4 page 408Review Example 9.1 page 409Try Practice Exercises 9.2/9.3 page 408Study and Answer Review Questions #9.3-#9.7 page 458Work End of Chapter Problems #9.73 -#9.90 pages 460-461 especially #9.81-9.82 and #9.83-9.84 page 461

Module 4iii Part N: Geometry of Molecules 1 pointUse the dot/stick structures on the Part L1 page to state the geometry of the molecules:Steric Numbers 2, 3, or 4:Trigonal Bent Linear Trigonal Planer Planer Trigonal Pyramidal Tetrahedral Steric Numbers 5 or 6:Trigonal-bipyramidal Square Planer Seesaw T-shaped Octahedral Other

_______________1. BrF3

_______________2. XeO4

_______________3. SO2

_______________4. SO3

_______________5. XeF4

_______________6. BrF5

_______________7. AsF5

_______________8. SeF6

_______________9. SeF4

_______________10. KrF2

_______________11. BrF3

_____________ Bonus C6H6

Benzene C6H6

Reading Reference: Jespersen 7th Section 9.1/9.2 See Example 9.1 Page 409 See Steps page 413; See Example 9.4 Page415Practice Exercise 9.1 page 406; Practice Exercises 9.2/9.3 Page 409; Practice Exercises9.4-9.6 Page 415Look at End of Chapter Exercises #9,1-#9,7 page 458; Wrk Review Problems #9.73-#9.82 page 460-1

Module 4iii Part O: Polarity of Molecules 1 pointSketch the 3D model of the molecule, show all dipoles; then decide if the molecule has a net dipole moment or not. Write Polar or Nonpolar in each blank.

_______________1. BrF3

_______________2. XeO4

_______________3. SO2

_______________4. SO3

_______________5. XeF4

_______________6. BrF5

_______________7. AsF5

_______________8. SeF6

_______________9. SeF4

_______________10. KrF2

_______________11. BrF3

_____________ Bonus C6H6

Benzene C6H6

Reading Reference: Section 8.6; Section 9.3See Example 9.5 page 419 Work Practice Exercises 9.7/9.8 Page 420Review Questions 9.8-9.15 pages 460-461Try Problems 9.85-9.90 especially 9.89 and 9.90

Module 4iii - Part P1: Hybrid Orbitals of Molecules 1 pointUse the dot/stick structures in the table to predict the hybrid orbitals that overlap to form the covalent bond:

_____________1. BrF3 the sigma bond between either Br-F

_____________2. XeO4 the sigma bond between either Xe=O_____________2a. XeO4 the pi bond between either Xe=O

_____________3. SO2 the sigma bond between either S=O_____________3a. SO2 the pi bond between either S=O

_____________4. SO3 the sigma bond between S=O_____________4a. SO2 the pi bond between S=O

____________ 5. XeF4 either sigma bond between any Xe-F

____________6. BrF5 either single (sigma) bond between Br-F

____________7. AsF5 the sigma bond between any of the As-F

____________8. SeF6 the sigma bond between any of the SeF6

___________ 9. SeF4 either sigma bond between the As-F

___________ __10. KrF2 the sigma bond between either F-F

_________ ____11. BrF3 either single (sigma) bond between Br-F

_____________ 12. ClF5 either sigma bond between any Cl-F

What is difference between a Sigma (σ) and a pi (π) bond? What is a delta(Δ) BondReading Reference Jespersen 7th : Section 9.5 and 9.6Try Practice Exercise 9.11 and 9.12 page 427; Look at Example 9.6 page 428 and 9.7 page 430-431Try Practice Exercise 9.14 and 9.15 Page 431 Study Example 9.8Page 432 Do Practice Exercises 9.16 and 9.17 page 433, the 9.20 and 9.21 page 440

Module 4iii - Part Q: Formal Charge 1 point1. Using the method of the octet rule, the following structure was drawn:

Assign the formal charge to each atom in the Lewis Structureby completing the table below:

Show the nonzero formal charges on the Lewis structure byPlacing them in circles alongside the atoms

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total SO-O=O-

Sum of the formal charges in the molecule = ______

2. Using the method of the formal charge, the following structure was drawn:

Assign the formal charge to each atom in the Lewis Structureby completing the table below:

Show the nonzero formal charges on the Lewis structure byPlacing them in circles alongside the atoms

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total S

O=O=O=

Sum of the formal charges in the molecule = ______

Explain why the structure in #2 is more preferred than #1!

3.Using the method of the octet rule, the following structure was drawn:

Assign the formal charge to each atom in the Lewis Structureby completing the table below:

Show the nonzero formal charges on the Lewis structure byPlacing them in circles alongside the atoms

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total S

O=O=-O-H--O-H-

Sum of the formal charges in the molecule = ______

4. Using the method of the octet rule, the following structure was drawn:

Assign the formal charge to each atom in the Lewis Structureby completing the table below:

Show the nonzero formal charges on the Lewis structure byPlacing them in circles alongside the atoms

FormalCharge = Valence

Electrons - NonbondingVal Electrons - Bonding e 1-

2 = Total S

-O-H--O-O-H--O

Sum of the formal charges in the molecule = ______

Explain why the structure in #4 is more preferred than #3!

Module 4iii - Part R: Resonance 1 point

1. Draw the Resonance Structures for Perchlorate Ion ClO41-

2. Draw the Resonance Structures for Phosphate Ion PO43-

3. Draw the Resonance Structures for Nitrite Ion NO21-

4. Draw the Resonance Structures for Benzene C6H6 ; show resonance hybrid

5. Draw the Resonance Structures for Carbonate Ion CO32-

Formal Charge References:Reading Reference Jespersen 7th : Section 8.7 pages 377-384Look at Calculating formal charges on an atom in a Lewis Structure page 379.Formula:

Jespersen’s Formula:

Look at Example 8.9 page 382-3Try Practice Exercise 8.18; 8.19 and 8.20 page 383Try Practice Exercise 8.21 and 8.22 Page 384

Do End of Chapter Qestions #8.44-#8.47 page 397Try Review Problems #8.105-#8.110 pages 399-400

Resonance References:Reading Reference Jespersen 7th : Section 8.8Look at Example 8.8 page 385 Try Practice Exercise 8.23; 8.24 and 8.25 page 386; Note the discussion on benzene on page 387Answer Review questions: #8.51-#8.54 page 397Try Review Problems: 8.113-8.118 page 400

Module 4iii - Part S: Sigma and Pi Bonds 1 point Note Figures 9.30 and 9.31 formation of Sigma σ and Pi π Bonds !

1. Sketch the hybrid orbitals for ethane (C2H4) showing the 5 sigma bonds (see Figure 9.32)

2. Sketch the p-p orbital overlap in ethane (figure 9.32 page 436)

3. Sketch the hybrid orbitals for formaldehyde (CH2O ) showing the 3 sigma bonds (see Figure 9.34)

4. Sketch the p-p orbital overlap in formaldehyde (CH2O ) (figure 9.34 page 438)

5. Sketch the hybrid orbitals for Acetylene (C2H2 ) showing the 3 sigma bonds (see Figure 9.35)

6. Sketch the p-p orbital overlap in Acetylene (C2H2 ) (figure 9.35 page 439)

Reading Reference Jespersen 7th: Section 9.6Note Brief Summary page 439.Try Practice Exercises 9.20 and 9.21 page 440Answer Review Questions # 9.30-#9.34 Page 409Try Review Problems #9.103-#9.110