Chemistry 51 ANSWER KEY REVIEW QUESTIONS Chapter 5 1. Binary Ionic – Type I Assign charges for each ion below, and complete the table with formulas and names for compounds formed by the combination of each cation and anion. S 2– Cl 1– N 3– O 2– Ca 2+ K 1+ Al 3+ Zn 2+ CaS K2S Al2S3 ZnS calcium sulfide potassium sulfide aluminum sulfide zinc sulfide CaCl2 KCl AlCl3 ZnCl2 calcium chloride potassium chloride aluminum chloride zinc chloride Ca3N2 K3N AlN Zn3N2 calcium nitride potassium nitride aluminum nitride zinc nitride CaO K2O Al2O3 ZnO calcium oxide potassium oxide aluminum oxide zinc oxide 2. Binary Ionic – Type II Based on the charges given for each cation, complete the table with formulas and names (Stock and Classical) for compounds formed by the combination of each cation and anion. I 1– P 3– O 2– Fe 2+ Cu 1+ Fe 3+ Sn 4+ FeI2 CuI FeI3 SnI4 iron (II) iodide copper (I) iodide iron (III) iodide tin (IV) iodide ferrous iodide cuprous iodide ferric iodide stannic iodide Fe3P2 Cu3P FeP Sn3P4 iron (II) phosphide ferrous phosphide copper (I) phosphide cuprous phosphide iron (III) phosphide tin (IV) phosphide stannic phosphide FeO Cu2O Fe2O3 SnO2 iron (II) oxide copper (I) oxide iron (III) oxide tin (IV) oxide ferrous oxide cuprous oxide ferric oxide stannic oxide
ferric phosphide 3. Polyatomic Assign charges for each ion below, and complete the table with formulas and names for compounds formed by the combination of each cation and anion. SO4 2– NO3 1– CO3 2– PO4 3– Ba 2+ Al 3+ NH4 1+ Pb 4+ BaSO4 Al2(SO4)3 (NH4)2SO4 Pb(SO4)2 barium sulfate aluminum sulfate ammonium sulfate lead (IV) sulfate Ba(NO3)2 Al(NO3)3 NH4NO3 Pb(NO3)4 barium nitrate aluminum nitrate ammonium nitrate lead (IV) nitrate BaCO3 Al2(CO3)3 (NH4)2CO3 Pb(CO3)2 barium carbonate aluminum carbonate ammonium carbonate lead (IV) carbonate Ba3(PO4)2 AlPO4 (NH4)3PO4 Ph3(PO4)4 barium phosphate aluminum phosphate ammonium phosphate lead (IV) phosphate 4. Covalent Complete the table below with missing formulas and names. iodine heptafluoride IF7 bromine trifluoride BrF3 N2O5 dinitrogen pentoxide OF2 oxygen difluoride disulfur hexachloride S2Cl6 SF4 sulfur tetrafluoride
2 5. Complete the following table with the missing information: Ion Number of Protons Number of Electrons Electrons Lost/Gained K + 19 18 1 Lost Mg 2+ 12 10 2 lost O 2– 8 10 2 gained Al 3+ 13 10 3 lost 6. Classify each of the following bonds as ionic, polar covalent or non­polar covalent: a) P¾F ionic (DEN = 1.9) b) Rb¾Cl ionic (DEN = 2.2) c) N¾O polar covalent (DEN = 0.5) 7. Arrange the following bonds in order of increasing polarity: N¾O Br¾Cl DEN 0.5 0.2 I¾I < Br¾Cl least polar C¾H I¾I Zn¾S Li¾F 0.4 0 0.9 3.0 < C¾H < N¾O < Zn¾S < 3 Li¾F most polar
8. Draw Lewis structures and use VSEPR to predict the shape and bond angles and polarity for each of the following molecules or ions: a) SO3 2– Shape: trigonal pyramidal Bond angle: 109.5° Polarity (Y/N): Yes b) OCl2 Shape: bent Bond angle: 109.5° Polarity (Y/N): Yes c) COCl2 Shape: trigonal planar Bond angle: 120° Polarity (Y/N): Yes (non­symmetrical) d) N3 – Shape: 4 linear Bond angle: 180° Polarity (Y/N): No
9. Write the formula for the ionic compound formed from the combination of the elements indicated by the following electron­dot symbols: a) X3Y b) XY c) XY3 10. Complete each of the following statements with a suitable word or phrase: a) Polarity of a bond is caused by difference in electronegativity b) Linear molecules with polar bonds are usually non­polar c) Molecules with 3 bonding pairs and 1 non­bonding pair of electrons around the central atom have a pyramidal shape. d) Bonds that have unequal sharing of electrons are classified as polar covalent e) Molecules with 2 bonding pairs and 2 non­bonding pair of electrons around the central atom have a shape.
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