Covalent BondingCovalent Bonding
8CHAPTERSOLUTIONS MANUALCovalent BondingSection 8.1 The Covalent Bond8. Describe how the octet rule applies to covalentpages 240–247bonds.Practice ProblemsAtoms share valence electrons; the sharedelectrons complete the octet of each atom.page 2449. Illustrate the formation of single, double, andDraw the Lewis structure for each molecule.1. PH3HHH— —HH— PPtriple covalent bonds using Lewis structures.Student Lewis structures should show thesharing of a single pair of electrons, two pairsof electrons, and three pairs of electrons,respectively, for single, double, and triplecovalent bonds.H10. Compare and contrast ionic bonds and cova2. H2SHH —SSValence electrons are involved in both types ofbonds. In covalent bonds, atoms share electrons,whereas is ionic bonds, electrons are transferredbetween atoms.—Hlent bonds.H3. HClH11. Contrast sigma bonds and pi bonds.H — ClClA sigma bond is a single covalent bond formedfrom the direct overlap of orbitals. A pi bond isthe parallel overlap of p orbitals.ClClClClC— —ClCl — C— ClCl5. SiH4—HHHHHSiH — Si — H—12. Apply Create a graph using the bond-dissociation energy data in Table 8.2 and thebond-length data in Table 8.1. Describe therelationship between bond length and bonddissociation energy.Student graphs should show that as bond lengthdecreases the bond dissociation energy increases.HCovalent Bond Length vs.Bond Dissociation Energy6. Challenge Draw a generic Lewis structure fora molecule formed between atoms of group 1and group 16 elements.Using 1 and 16 to represent atoms of groups 1and 16, respectively, the generic structure is:Section 8.1 Assessmentpage 2477. Identify the type of atom that generally formscovalent bonds.The majority of covalent bonds form betweennonmetallic elements.Solutions Manual1000Bond DissociationEnergy (kJ/mol)Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.4. CCl4800600400200011.11.21.3Covalent Bond Length1.41.5(10 –10m)Chemistry: Matter and Change Chapter 8121
CHAPTER813. Predict the relative bond energies needed tobreak the bonds in the structures below.a. H — C ——C —HC—H: less energy than C CSOLUTIONS MANUAL22. H2SO4sulfuric acid23. H2Shydrosulfuric acidH— —— —b. HC—CHH24. Challenge What is the formula for periodicacid?HIO4C—H: less energy than C Cpages 248–252Practice Problemspages 249–251Name each of the binary covalent compoundslisted below.14. CO2carbon dioxide15. SO2sulfur dioxide16. NF3nitrogen trifluoride17. CCl4carbon tetrachloride18. Challenge What is the formula for diarsenictrioxide?Ar 2O 3Name the following acids. Assume eachcompound is dissolved in water.19. HIhydroiodic acid20. HClO3AgCl26. dihydrogen oxideH2O27. chlorine trifluorideClF328. diphosphorus trioxideP2O329. disulfur decafluorideS2F1030. Challenge What is the formula for carbonicacid?H2CO3Section 8.2 Assessmentpage 25231. Summarize the rules for naming binarymolecular compounds.Name the first element in the formula first. Namethe second element using its root plus thesuffix –ide. Add prefixes to indicate the numberof atoms of each element present.32. Define a binary molecular compound.a molecule composed of only two nonmetalelementschloric acid21. HClO2chlorous acid122Chemistry: Matter and Change Chapter 833. Describe the difference between a binary acidand an oxyacid.A binary acid contains hydrogen and one otherelement. An oxyacid contains hydrogen, anotherelement, and oxygen.Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.Section 8.2 Naming MoleculesGive the formula for each compound.25. silver chloride
CHAPTER8SOLUTIONS MANUAL34. Apply Using the system of rules for namingbinary molecular compounds, describe how youwould name the molecule N2O4.38. Challenge A nitrogen trifluoride moleculecontains numerous lone pairs. Draw its Lewisstructure.There are two atoms of nitrogen; use the prefixdi– with the name nitrogen. There are four atomsof oxygen, so use the prefix tetra– the root ofoxygen the ending –ide. The name is dinitrogentetroxide.—F—N—35. Apply Write the molecular formula for each ofFF39. Draw the Lewis structure for ethylene, C2H4.Hthese compounds:, iodic acid, disulfur trioxide,dinitrogen monoxide, hydrofluoric acid.HHIO3, S2O3, N2O, HF36. State the molecular formula for eachcompound listed below.a. dinitrogen trioxideCCHH40. Challenge A molecule of carbon disulfidecontains both lone pairs and multiple-covalentbonds. Draw its Lewis structure.S—C—SN2O341. Draw the Lewis structure for ethylene,b. nitrogen monoxideNH4 ion.NO1 Hc. hydrochloric acidHNHHd. chloric acid42. Challenge The ClO4– ion contains numerousHClO3lone pairs. Draw its Lewis structure.e. sulfuric acidO1—H2SO4O — Cl — Of. sulfurous acid—Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.HClOH2SO3Section 8.3 Molecular Structurespages 253–260Draw the Lewis resonance structures for thefollowing molecules.43. NO2 1 1 Practice Problemspages 255–260ONOONO37. Draw the Lewis structure for BH3.44. SO2H—H—Solutions ManualB—HOSOOSOChemistry: Matter and Change Chapter 8123
CHAPTER8SOLUTIONS MANUAL45. O351. State the steps used to draw Lewis structures.OOOO46. Challenge Draw the Lewis resonancestructure for the ion SO32 .SO2–52. Summarize exceptions to the octet rule byOS O 2–Oexpanded octet, PCl5; odd number of valenceelectrons, ClO2; less than an octet, BH3OSOO2–ODraw the expanded octet Lewis structure of eachmolecule.47. ClF3Fcorrectly pairing these molecules and phrases:odd number of valence electrons, PCl5, ClO2,BH3, expanded octet, less than an octet.FClF53. Evaluate A classmate states that a binarycompound having only sigma bonds displaysresonance. Could the classmate’s statementbe true?No, a molecule or polyatomic ion must haveboth a single bond and a double bond in orderto display resonance. Only single bonds can besigma bonds.54. Draw the resonance structures for thedinitrogen oxide (N2O) molecule. orN N O N N—O 48. PCl5ClClPClClCl55. Draw the Lewis structure for CN , SiF4,HCO3 , and AsF6 .CN :N ] [C49. Challenge Draw the Lewis structure for themolecule formed when six fluorine atoms andone sulfur atom bond covalently.FSiFSiF4 :FFSFFFFFFSection 8.3 Assessment OHCO3 :HCOOpage 26050. Describe the information contained in astructural formula.types of atoms, number of atoms, and a roughapproximation of the molecular shape FAsF6 :FFAsFFF124Chemistry: Matter and Change Chapter 8Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.O1) determine central atom and terminalatoms, 2) determine number of bondingelectrons, 3) determine bonding pairs, 4) connectterminal atoms to the central atom with singlebonds, 5) determine remaining number ofbonding pairs, 6) apply octet rule and formdouble or triple bonds if needed OO
8CHAPTERSOLUTIONS MANUALSection 8.4 Molecular ShapesPractice Problemspage 264Determine the molecular shape, bond angle, andhybrid orbitals for each molecule.56. BF3trigonal planar, 120 , sp2FBF63. Describe how the presence of a lone pairaffects the spacing of shared bonding orbitals.A lone pair occupies more space than a sharedelectron pair, thus, the presence of a lone pairpushes the bonding pairs closer together.64. Compare the size of an orbital that has ashared electron pair with one that has a lonepair.The orbital containing a lone electron pairoccupies more space than a shared electron pair.F65. Identify the type of hybrid orbitals present and57. OCl2bent, 104.5 , sp3OCl58. BeF2ClBeFtetrahedral, 109 , sp3FFCForbitals of PF3 and PF5 molecules. Explain whytheir shapes differ.PF3 is trigonal pyramidal with sp3 hybrid orbitals.PF5 is trigonal bipyramidal with sp3d hybridorbitals. Shape is determined by the type ofhybrid orbital.67. List in a table, the Lewis structure, molecularFCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.sp3 and 109 66. Compare the molecular shapes and hybridlinear, 180 , spF59. CF4bond angles for a molecule with a tetrahedralshape. 60. Challenge For the NH4 ion, identify itsmolecular shape, bond angle, and hybridorbitals.shape, bond angle, and hybrid orbitals formolecules of CS2, CH2O, H2Se, CCl2F2,and NCl3.CS2:tetrahedral, 109 , sp3S C SH1 HCH2O:H—N—HHH2Se:CCI2F2:61. Summarize the VSEPR bonding theory.VSEPR theory determines molecular geometrybased on the repulsive nature of electron pairsaround a central atom.Htrigonal planar,120 , sp2C OSeHbent, 104.5 , sp3ClSection 8.4 Assessmentpage 264Hlinear, 180 , spCl CFtetrahedryl,109 , sp3FNCL3:ClCl Ntrigonal pyramidal,107 , sp3Cl62. Define the term bond angle.The bond angle is the angle formed by any twoterminal atoms and the central atom.Solutions ManualChemistry: Matter and Change Chapter 8125
CHAPTER8Section 8.5 Electronegativityand Polaritypages 265–270Section 8.5 Assessmentpage 27068. Summarize how electronegativity differenceis related to bond character.The greater the electronegativity difference, thegreater the ionic nature of the bond.69. Describe a polar covalent bond.A polar covalent bond has unequal sharing ofelectrons. The electrons are pulled toward oneof the atoms, generating partial charges on theends.70. Describe a polar molecule.A polar molecule is one that has a greaterelectron density on one side of the molecule.71. List three properties of a covalent compound inSOLUTIONS MANUALb. C and Helectronegativity of C 2.55;electronegativity of H 2.20;EN difference 0.35; mostly covalentc. Na and S.electronegativity of S 2.58;electronegativity of Na 0.93;EN difference 1.65; polar covalent75. Identify each molecule as polar or nonpolar:SCl2, CS2, and CF4.SCl2, polar; CS2, nonpolar; CF4, nonpolar76. Determine whether a compound made ofhydrogen and sulfur atoms is polar or nonpolar.hydrogen and sulfur form H2S, a molecule witha bent shape; the molecule is polar because it isasymmetric77. Draw the Lewis structures for the moleculesSF4 and SF6. Analyze each structure to determine whether the molecule is polar or nonpolar.the solid phase.FFFSSFFFFFFF72. Categorize bond types using electronegativitySF4: polardifference.If the difference is zero, the bond is considerednonpolar covalent; if between zero and 0.4,mostly covalent; if between 0.4 and 1.7, polarcovalent; if greater than 1.7, mostly ionic.73. Generalize Describe the generalcharacteristics of covalent network solids.brittle, nonconductors of heat and electricity,extremely hard74. Predict the type of bond that will formbetween the following pair of atoms:a. H and Selectronegativity of S 2.58electronegativity of H 2.20EN difference 0.38; mostly covalentSF6: nonpolarChapter 8 Assessmentpages 274–277Section 8.1Mastering Concepts78. What is the octet rule, and how is it used incovalent bonding?Atoms lose, gain, or share electrons to end witha full outer energy level of eight electrons.Covalent bonding occurs when atoms shareelectrons to achieve an octet.79. Describe the formation of a covalent bond.The nucleus of one atom attracts the electrons ofthe other atom, and they share one or more pairsof electrons.126Chemistry: Matter and Change Chapter 8Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.The solid state of a molecule is crystalline. Amolecular solid is soft, a nonconductor, and has alow melting point.
8below:repulsive, that occur as two atoms comecloser together.Attractive forces occur between the nucleus ofone atom and the electrons of the other atom.Repulsive forces occur between the nuclei ofthe two atoms and between the electrons ofthe two atoms. As the atoms approach, the netforce of attraction increases. At a certain optimaldistance between atoms, the net attractive forceis maximized. If the atoms move closer thanthe optimal distance, repulsive force exceedsattractive force. See Figure 8.2 on page 241.82. How could you predict the presence of a sigmaor pi bond in a molecule?Mastering Problems83. Give the number of valence electrons in N,As, Br, and Se. Predict the number of covalentbonds needed for each of these elements tosatisfy the octet rule.N: 5, 3; As: 5, 3; Br: 7, 1; Se: 6, 284. Locate the sigma and pi bonds in each of themolecules shown below.a.O—Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.A single covalent bond is always a sigma bond;a double bond consists of a sigma bond and api bond; a triple bond consists of one sigma andtwo pi bonds.H—C—Hsingle bonds: sigma bonds; double bond: onesigma bond and one pi bondb. H — C ——C —Hsingle bonds: sigma bonds; triple bond: one sigmaand two pi bonds85. In the molecules CO, CO2, and CH2O, whichC—O bond is the shortest? Which C—O bondis the strongest?The triple bond in CO is the shortest and thestrongest.Solutions ManualHH—C N- and81. Describe the forces, both attractive andH —C —N—Molecules bond covalently.86. Consider the carbon-nitrogen bonds shown—80. Describe the bonding in molecules.SOLUTIONS MANUAL—CHAPTERHHWhich bond is shorter? Which is stronger?The triple bond in C N is shorter and stronger.87. Rank each of the molecules below in order ofthe shortest to the longest sulfur-oxygen bondlength.a. SO2b. SO32 c. SO42 a, c, bSection 8.2Mastering Concepts88. Explain how molecular compounds are named.Naming follows a specific set of rules dependingon whether the compound forms an acidicaqueous solution. Answers should agree withFigure 8.12 on page 252.89. When is a molecular compound named asan acid?when it releases H in water solution90. Explain the difference between sulfurhexafluoride and disulfur tetrafluoride.Sulfur hexafluoride is SF6, which has one atom ofsulfur bonded with six atoms of fluorine. Disulfurtetrafluoride is S2F4, which has two atoms ofsulfur bonded with four atoms of fluorine.91. Watches The quartz crystals used in watchesare made of silicon dioxide. Explain how youuse the name to determine the formula forsilicon dioxideThe name silicon indicates one atom of Si. Theprefix di- means two and oxide indicates oxygen.The correct formula is SiO2.Chemistry: Matter and Change Chapter 8127
8SOLUTIONS MANUALMastering Problems92. Complete Table 8.8.c. carbon tetrafluorideCF4d. sulfurous acidAcid NamesFormulaNameHClO2chlorous acidH3PO4phosphoric acidH2Sehydroselenic acidHClO3chloric acid93. Name each molecule.a. NF3nitrogen trifluorideb. NOnitrogen monoxidec. SO3sulfur trioxided. SiF4silicon tetrafluoride94. Name each molecule.a. SeO2selenium dioxideb. SeO3selenium trioxidec. N2F4dinitrogen tetrafluorided. S4N4tetrasulfur tetranitride95. Write the formula for each molecule.a. sulfur difluorideSF2b. silicon tetrachlorideSiCl4128Chemistry: Matter and Change Chapter 8H2SO396. Write the formula for each molecule.a. silicon dioxideSiO2b. bromous acidHBrO2c. chlorine trifluorideClF3d. hydrobromic acidHBrSection 8.3Mastering Concepts97. What must you know in order to draw theLewis structure for a molecule?the number of valence electrons for each atom98. Doping Agent Material scientists arestudying the properties of polymer plasticsdoped with AsF5. Explain why the compoundAsF5 is an exception to the octet rule.Arsenic has five bonding positions with a totalof 10 shared electrons. This is greater that theeight electrons that occupy an octet.99. Reducing Agent Boron trihydride (BH3) isused as reducing agent in organic chemistry.Explain why BH3 often forms coordinatecovalent bonds with other molecules.BH3 only has 6 electrons and does not havean electron arrangement with a low amountof potential energy. It will share a lone pairwith another molecule to form this electronarrangement.Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.CHAPTER
8SOLUTIONS MANUAL100. Antimony and chlorine can form antimonytrichloride and antimony pentachloride.Explain how these elements are able to formtwo different compounds.103. Draw two resonance structures for thepolyatomic ion HCO2 .C O HAntimony has five valence electrons, one lonepair, and three positions where it can share oneelectron with a chlorine atom. This will formSbCl3. Antimony can also expand its octet andbond with all five valence electrons, formingSbCl5.OHO C CHAPTERO104. Draw the Lewis structure for a molecule ofMastering Problems101. Draw three resonance structures for thepolyatomic ion CO32 .O COHS2 HOb. BF4 C OOeach of these compounds and ions.a. H2S F2 FOBFFO CO2 c. SO2Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.OO S102. Draw the Lewis structure for these molecules,each of which has a central atom that does notobey the octet rule.a. PCl5ClClClOd. SeCl2ClP ClSeClCl105. Which elements in the list below are capableb. BF3FFBFc. ClF5FFClFFFof forming molecules in which one of itsatoms has an expanded octet? Explain youranswer.a. Bb. Cc. Pd. Oe. SeP and Se because they are from period 3 orhigher and have a d sublevel availabled. BeH2H—Be—HSolutions ManualChemistry: Matter and Change Chapter 8129
CHAPTER8Section 8.4Mastering Concepts106. What is the basis of the VSEPR model?the repulsive nature of electron pairs around acentral atom107. What is the maximum number of hybridorbitals a carbon atom can form?SOLUTIONS MANUALMastering Problems110. Complete Table 8.9 by identifying theexpected hybrid on the central atom. Youmight find drawing the molecule’s Lewisstructure helpful.StructuresFormulaHybrid OrbitalXeF4sp3d2Lewis StructureFfour108. What is the molecular shape of each molecule?Estimate the bond angle for each molecule,assuming that there is not a lone pair.a. A—Blinear, 180 b. inear, 180 111. Predict the molecular shape of each molecule.—a. COSAlineartrigonal planar, 120 A— —d.A—B—AAtetrahedral, 109 109. Parent Compound PCl5 is used as a parentcompound to form many other compounds.Explain the theory of hybridization anddetermine the number of hybrid orbitalspresent in a molecule of PCl5.The theory of hybridization explains the shapesof molecules by the formation of identical hybridorbitals from the atomic orbitals of the atoms inthe molecule; five identical sp3d orbitalsb. CF2Cl2tetrahedral112. For each molecule listed below, predict itsmolecular shape and bond angle, and identifythe hybrid orbitals. Drawing the Lewisstructure might help you.a. SCl2bent, 104.5 , sp3b. NH2Cltrigonal pyramidal, 107 , sp3c. HOFbent, 104.5 , sp3d. BF3trigonal planar, 120 , sp2130Chemistry: Matter and Change Chapter 8Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.c. A—B—A
CHAPTER8Section 8.5Mastering Concepts113. Describe electronegativity trends in theperiodic table.It increases left to right in a period anddecreases top to bottom in a group.114. Explain the difference between nonpolarmolecules and polar molecules.A nonpolar molecule has a symmetricdistribution of charge, while a polar moleculehas a concentration of electrons on one side ofthe molecule.115. Compare the location of bonding electrons ina polar covalent bond with those in a nonpolarcovalent bond. Explain your answer.Electrons in a polar bond are closer to themore electronegative atom because of unequalsharing. Those in a nonpolar bond are sharedequally.Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.116. What is the difference between a covalentmolecular solid and a covalent network solid?Do their physical properties differ? Explainyour answer.A covalent molecular solid is soft and has a lowmelting point because of weak intermolecularforces. A covalent network solid has a highmelting point and is very hard because of thestrength of the network of covalent bonds.Mastering Problems117. For each pair, indicate the more polar bond bycircling the negative end of its dipole.a. C—S, C—OO is circled because it has the greatestelectronegativity. C—O is the more polarbond. There is a greater electronegativitydifference between C and O.Electronegativity S 2.58; electronegativityC 2.55; EN difference 0.03;electronegativity O 3.44; electronegativityC 2.55; EN difference 0.89Solutions ManualSOLUTIONS MANUALb. C—F, C—NF is circled because it has the greatestelectronegativity. C—F is the more polarbond. There is a greater electronegativitydifference between C and F. ElectronegativityF 3.98; electronegativity C 2.55;EN difference 1.43. ElectronegativityN 3.04; electronegativity C 2.55; ENdifference 0.49c. P—H, P—ClCl is circled because it has the greatestelectronegativity. P—Cl is the more polarbond. There is a greater electronegativitydifference between Cl and P. ElectronegativityH 2.20; electronegativityP 2.19; EN difference 0.01.Electronegativity Cl 3.16; electronegativityP 2.19; EN difference 0.97118. For each of the bonds listed, tell which atom ismore negatively charged.The most negatively charged atom has thegreatest electronegativity. Use Figure 8.20.a. C—HCb. C—NNc. C—SSd. C—OO119. Predict which bond is the most polar.a. C—Oelectronegativity O 3.44, electronegativityC 2.55, EN difference 0.89b. Si—Oelectronegativity O 3.44, electronegativitySi 1.90, EN difference 1.54Chemistry: Matter and Change Chapter 8131
CHAPTER8c. C—Clelectronegativity Cl 3.16, electronegativityC 2.55, EN difference 0.61d. C—Brelectronegativity Br 2.96, electronegativityC 2.55, EN difference 0.41Si—O is the most polar because it has thegreatest electronegativity difference.120. Rank the bonds according to increasingpolarity.a. C—Helectronegativity C 2.55, electronegativityH 2.20, EN difference 0.35SOLUTIONS MANUALc. H2Spolar, asymmetricald. CF4nonpolar, symmetrical123. Use Lewis structures to predict the molecularpolarities for sulfur difluoride, sulfurtetrafluoride, and sulfur hexafluoride.SF2 and SF4 are polar. SF6 is nonpolar.Mixed Review124. Write the formula for each molecule.a. chlorine monoxideClOb. N—Hc. Si—Helectronegativity H 2.20, electronegativitySi 1.90, EN difference 0.30d. O—Helectronegativity O 3.44, electronegativityH 2.20, EN difference 1.24e. Cl—Helectronegativity Cl 3.16, electronegativityH 2.20, EN difference 0.96in order of increasing polarity: c, a, b, e, d121. Refrigerant The refrigerant known as freon-14 is an ozone-damaging compound withthe formula CF4. Why is the CF4 moleculenonpolar even though it contains polar bonds?equal distribution of charge in a symmetricalmolecule122. Determine if these molecules and ion arepolar. Explain your answers.a. H3O polar, asymmetricalb. PCl5b. arsenic acidH3AsO4c. phosphorus pentachloridePCl5d. hydrosulfuric acidH2S125. Name each molecule.a. PCl3phosphorus trichlorideb. Cl2O7dichlorine heptoxidec. P4O6tetraphosphorus hexoxided. NOnitrogen monoxide126. Draw the Lewis structure for each moleculeor ion.a. SeF2FSeFnonpolar, symmetrical132Chemistry: Matter and Change Chapter 8Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.electronegativity N 3.04, electronegativityH 2.20, EN difference 0.84
CHAPTER8SOLUTIONS MANUALb. ClO2 c. Ge—Oelectronegativity O 3.44, electronegativityGe 2.01, difference 1.43O Cl Od. C—Clelectronegativity Cl 3.16, electronegativityCP 2.55, difference 0.61c. PO33 OPO3 e. C—Brelectronegativity Br 2.96, electronegativityC 2.55, difference 0.41Oin order of least to greatest polar bondcharacter is the same as the order ofincreasing electronegativity differences(refer to Figure 8.21): e, d, a, c, bd. POCl3ClClPO129. Rocket Fuel In the 1950s, the reaction ofClhydrazine with chlorine trifluoride (ClF3) wasused as a rocket fuel. Draw the Lewis structurefor ClF3 and identify the hybrid orbitals.e. GeF4FFFGeFFCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.Cl127. Determine which of the molecules are polar.Explain your answer.a. CH3Clb. ClFc. NCl3d. BF3e. CS2The polar molecules are CH3Cl, ClF, and NCl3because each molecule is asymmetric and thecharge is not distributed evenly.128. Arrange the bonds in order of least togreatest polar character.a. C—Oelectronegativity O 3.44, electronegativityC 2.55, difference 0.89FFsp3d130. Complete Table 8.10, which shows thenumber of electrons shared in a single covalent bond, a double covalent bond, and a triplecovalent bond. Identify the group of atoms thatwill form each of these bonds.Shared PairsNumber of SharedElectronsAtoms that Formthe BondSinglecovalent2 shared electronsany halogen, group17Doublecovalent4 shared electronsA group 16elementTriplecovalent6 shared electronsA group 15elementBond Typeb. Si—Oelectronegativity O 3.44, electronegativitySi 1.90, difference 1.54Solutions ManualChemistry: Matter and Change Chapter 8133
8SOLUTIONS MANUALThink Critically131. Organize Design a concept map that explainsNhow VSEPR model theory, hybridizationtheory, and molecular shape are related.132. Compare and contrast the two compoundsidentified by the names arsenic(III) oxide anddiarsenic trioxide.The name arsenic(III) oxide states that arsenichas an oxidation number of 3 and oxide is 2 .The correct formula is As2O3. The name diarsenictrioxide states that there are two atoms of arsenicand three atoms of oxygen. The correct formulais As2O3. Even though they are named differently,they both represent the same formula.133. Make and Use Tables Complete Table 8.11using Chapters 7 and 8.CovalentmolecularMetallicCovalentnetworkCNHSigma bonds are the N—H bonds and the C—Nbonds as well as one of the C—O bonds. Theother C—O bond is a pi bond. The lone pairs arelocated on both N atoms and on the O atom.135. Analyze For each of the characteristics listedbelow, identify the polarity of a molecule withthat characteristic.a. a solid at room temperaturepolarb. a gas at room temperaturenonpolarc. attracted to an electric currentpolarBondDescriptionCharacteristicof Solidthe electrostaticattraction ofa positive ionfor a negative ionhard, rigid, brittle, crystalline,high meltingpoint, nonconductor in thesolid stateNaClsoft, low meltthe sharinging point,of electronsbetween two non-conductorin the solid stateatomsCO2Example136. Apply The structural formula for acetonitrile,CH3CN, is shown below.HH CHC——Nthe attractionof a positive ion fordelocalizedelectronsa crystal thatconducts heatand electricity, malleable,ductile, highmelting pointAgExamine the structure of acetonitrile molecule.Determine the number of carbon atoms in themolecule, identify the hybrid present in eachcarbon atom, and explain your reasoning.atoms covalently bondedto manyother atomscrystal is hard,rigid, brittle,nonconductordiamondThe first carbon (bonded to three H atoms andone C atom) atom is a sp3 hybrid because ithas 4 bonding positions. The 2nd carbon atom(bonded to one C atom and one N atom) is an sphybrid because it has two bonding positions.134. Apply Urea, whose structure is shown in theChallenge Problem137. Examine the bond-dissociation energies for thevarious bonds listed in Table 8.12.next column, is a compound used in manufacturing plastics and fertilizers. Identify the sigmabond, pi bonds, and lone pairs present in amolecule of urea.134Chemistry: Matter and Change Chapter 8Solutions ManualCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.IonicHHConcept maps will vary.SolidOH—CHAPTER
8CHAPTERSOLUTIONS MANUALO—C—OBond-Dissociation EnergiesBondBondDissociationEnergy (kJ/mol)Cl — C — Cl348O H467ClC C614C N305C C839O O498N N163C H416N N418C O358N N945C O745a. Draw the correct Lewis structures for C2H2and HCOOH.HC CF — Be — Fslope y23.40 g 14.04 g 2.34 g/mL x10.0 mL 6.0 mLThe unit of the slope is g/mL, which is the unitof density. The slope gives you the density ofthe liquid.139. Write the correct chemical formula for eachHcompound. (Chapter 7)a. calcium carbonateOH—C CH—BondBondDissociationEnergy (kJ/mol)CaCO3COb. potassium chlorateHKClO3b. Determine the amount of energy needed tobreak apart each of these molecules.Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.C2H2: (416 2) 839 kJ/mol 1671 kJ/molHCOOH: 416 745 358 467 kJ/mol 1986 kJ/molCumulative Review138. Table 8.13 lists a liquid’s mass and volumedata. Create a line graph of this data with thevolume on the x-axis and the mass on they-axis. Calculate the slope of the line. Whatinformation does the slope give you?(Chapter 2)c. silver acetateAgC2H3O2d. copper(II) sulfateCuSO4e. ammonium phosphate(NH4)3PO4140. Write the correct chemical name for eachcompound.a. NaIsodium iodideb. Fe(NO3)3Mass v. VolumeVolumeMass4.1 mL9.36 g6.0 mL14.04 g8.0 mL18.72 g10.0 mL23.40 giron(III) nitratec. Sr(OH)2strontium hydroxided. CoCl2cobalt(II) chloridee. Mg(BrO3)2magnesium bromateSolutions ManualChemistry: Matter and Change Chapter 8135
8CHAPTERSOLUTIONS MANUALAdditional AssessmentWriting in Chemistry141. Antifreeze Research ethylene glycol, anantifreeze-coolant, to learn its chemicalformula. Explain how its structure makes it auseful antifreeze and coolant.OHCCHHObHAnswers will vary. Students might note that thepresence of –OH groups make ethylene glycolmiscible in water and contribute to its relativelyhigh boiling point and relatively low freezingpoint.142. Detergents Choose a laundry detergent toresearch and write an essay about its chemicalcomposition. Explain how it removes oil andgrease from of fabrics.Answers should include a discussion of thenonpolar end of a detergent molecule and thepolar end of the same molecule allowing it toattract both water and oil.Document-Based Questionsc143. Determine the molecular formula for luminoland draw its Lewis structure.C8H7O2N3144. Indicate the hybrid present on the atomslabeled A, B, and C in Figure 8.26.a, sp2; b, sp3; c, sp2145. When luminol comes in contact with theiron ion in hemoglobin, it reacts to produceNa2APA, water, nitrogen, and light energy.Given the structural formula of the APA ionin Figure 8.27, write the chemical formula forthe polyatomic APA ion.Luminol Crime-
Draw the Lewis structure for BH 3. H —H H B — — 38. Challenge A nitrogen trifluoride molecule contains numerous lone pairs. Draw its Lewis structure. — N — — F F F 39. Draw the Lewis structure for ethylene, C 2 H 4. CC H H H H 40. Challenge A molecule of carbon disulfide contains both lone pairs and multiple-covalent bonds. Draw its .
Covalent Bonding 1. What is covalent bonding? 2. Ionic or covalent? a. CH 4 ionic or covalent b. Fe 2 O 3 ionic or covalent c. I 2 ionic or covalent d. H 2 O ionic or covalent e. BeCl 2 ionic or covalent 3. Lewis dot structures Helpful hints: Least electronegative compound goes in the middle
Chem 103, Section F0F Unit VI - Compounds Part II: Covalent Compounds Lecture 15 The formation of covalent bonds Naming binary covalent and organic compounds The covalent bonding model Lecture 15 - Covalent Bonding Reading in Silberberg Chapter 2, Section 7 (pp. 62-64)-The Formation of Covalent Compounds Chapter 2, Section 8 (pp. 70-72)-Compounds, Formulas and Names
Chapter 8 Covalent Bonding 8.1 Molecular Compounds 8.2 The Nature of Covalent Bonding 8.3 Bonding Theories 8.4 Polar Bonds and Molecules . . type of covalent bonding different from that seen in water, ammonia, methane, and carbon
Pure covalent bonding only occurs when two nonmetal atoms of the same kind bind to each other. When two different nonmetal atoms are bonded or a nonmetal and a metal are bonded, then the bond is a mixture of cova-lent and ionic bonding called polar covalent bonding. Covalent Bonding In METALLIC BONDING the valence electrons are
A)Metallic bonding B)hydrogen bonding C)covalent bonding D)ionic bonding 26.The particle diagram below represents a solid sample of silver. Which type of bonding is present when valence electrons move within the sample? A)ionic B)metallic C)nonpolar covalent D)polar covalent 27.Which type of bonding is present in a sample of an element that is .
What is a coordinate covalent bond? A coordinate covalent bond is an atom in which one atom provides both bonding electrons Example - Carbon monoxide. How does bonding in carbon monoxide work? Once a coordinate covalent bond forms, it is like any other covalent bond. It is often drawn as an arrow in a structural formula
2 Ionic/Covalent Beryllium nitride Li 2S Ionic/Covalent Lithium sulphide B 2O 3 Ionic/Covalent Diboron trioxide CaBr 2 Ionic/Covalent Calcium bromide Si 2Cl 6 Ionic/Covalent Disilicon hexachloride N 4S 5 Ionic/Covalent Tetranitrogen pentasulfide 2.Determine if the compound is ionic or covalent
Covalent Bonding Note: Students and classrooms with iPads should download the free "Lewis Dots" App and can use that on all the slides where Lewis Dot drawings are to be done. Slide 3 / 186 Table of Contents: Covalent Bonding · Properties of Ionic and Covalent Materials Click on the topic to go to that section · Naming Binary Molecular Compounds
