Honors Chemistry Chapter 9 Chemical Bonding I: Lewis Theory Name ______________________________ Period _____ Date ___________ 1. Identify the compound with ionic bonding. A) NaCl C) H2O B) Li D) He E) S 2. Identify the compound with covalent bonding. A) NaCl C) H2O B) Li D) He E) S 3. Identify the compound with metallic bonding. A) NaCl C) H2O B) Li D) He E) S 4. Which of the following statements is TRUE? A) A covalent bond is formed through the transfer of electrons from one atom to another. B) A pair of electrons involved in a covalent bond are sometimes referred to as "lone pairs." C) It is not possible for two atoms to share more than two electrons. D) Single bonds are shorter than double bonds. E) A covalent bond has a lower potential energy than the two separate atoms. 5. Which of the following represent the Lewis structure for N? A) B) E) C) D) 6. Which of the following represent the Lewis structure for Ca2⁺? A) B) E) C) D) 7. Identify the substance that conducts electricity. A) NaCl dissolved in water B) solid NaCl C) water D) solid sugar E) sugar dissolved in water. 8. Use Lewis theory to determine the chemical formula for the compound formed between Ca and N. A) CaN C) CaN2 E) Ca2N3 B) Ca3N2 D) Ca2N 9. Which of the following reactions is associated with the lattice energy of Li2O (ΔH°latt)? A) Li2O(s) → 2 Li⁺(g) + O2⁻(g) D) Li2O(s) → 2 Li⁺(aq) + O2⁻(aq) B) 2 Li⁺(aq) + O2⁻(aq) → Li2O(s) C) 2 Li⁺(g) + O2⁻(g) → Li2O(s) E) 2 Li(s) + ½ O2(g) → Li2O(s) 10. A double covalent bond contains __________ of electrons. A) 0 pairs C) 2 pairs B) 1 pair D) 3 pairs E) 4 pairs 11. Choose the compound below that should have the highest melting point according to the ionic bonding model. A) SrI2 C) CaCl2 E) SrBr2 MgF SrF B) 2 D) 2 12. Place the following in order of decreasing magnitude of lattice energy. K2O Rb2S Li2O A) Li2O > K2O > Rb2S D) Rb2S > Li2O > K2O B) Li2O > Rb2S > K2O E) K2O > Li2O > Rb2S C) Rb2S > K2O > Li2O 13. Give the complete electronic configuration for Ca2+. A) 1s22s22p63s24p6 B) 1s22s22p63s23p6 C) 1s22s22p63s23p5 D) 1s22s23p64s25p6 E) 1s22s2p63s2p6 14. Identify the shortest bond. A) single covalent bond B) double covalent bond C) triple covalent bond D) all of the above bonds are the same length 15. Identify the weakest bond. A) single covalent bond B) double covalent bond C) triple covalent bond D) all of the above bonds are the same strength 16. Identify the number of bonding pairs and lone pairs of electrons in water. A) 1 bonding pair and 1 lone pair D) 2 bonding pairs and 1 lone pair B) 1 bonding pair and 2 lone pairs E) 3 bonding pairs and 2 lone pairs C) 2 bonding pairs and 2 lone pairs 17. Place the following elements in order of increasing electronegativity. Sr N Na A) Sr < Na < N D) N < Sr < Na B) Na < N < Sr E) N < Na < Sr C) Sr < N < Na 18. Choose the bond below that is most polar. A) C-N C) C-O B) C-F D) C-C E) F-F 19. Using periodic trends, place the following bonds in order of increasing ionic character. S-F Se-F O-F A) Se-F < S-F < O-F D) Se-F < O-F < S-F B) S-F < Se-F < O-F E) O-F < S-F < Se-F C) O-F < Se-F < S-F 20. Which molecule or compound below contains a pure covalent bond? A) Li2CO3 C) Cl2 B) SCl6 D) PF3 E) NaCl 21. Which molecule or compound below contains a polar covalent bond? C) LiI A) C2H4 B) ZnS D) NCl3 E) AgCl 22. Which molecule or compound below contains an ionic bond? A) CO2 C) SiF4 C Cl B) 2 4 D) OCl2 E) NH4NO3 2 23. Choose the best Lewis structure for BeF2. A) C) B) D) E) 24. Give the number of valence electrons for XeI2. A) 22 B) 20 C) 18 D) 24 25. Choose the best Lewis structure for ICl5. A) B) E) C) D) 26. Choose the best Lewis structure for NO3⁻. A) C) E) D) B) 27. Which of the following resonance structures for OCN⁻ will contribute most to the correct structure of OCN⁻? A) O(2 lone pairs)=C=N (2 lone pairs) B) O(1 lone pair)≡C-N(3 lone pairs) C) O(1 lone pair)=C(2 lp)=N(1 lone pair) D) O(3 lone pairs)-C≡N(with 1 lone pair) E) They all contribute equally to the correct structure of OCN⁻. 28. Draw the best Lewis structure for CH3-1 to determine the formal charge on the C? A) 0 B) 1 C) -1 D) 2 29. Draw the Lewis structure for SO42⁻. How many equivalent resonance structures can be drawn? A) 6 C) 4 E) 8 B) 2 D) 3 30. Which of the following elements can form compounds with an expanded octet? A) N C) F E) None of the above can form B) Br D) Be compounds with an expanded octet. 3 31. How many of the following elements can form compounds with an expanded octet? Pb Kr Si B A) 0 C) 2 E) 4 B) 1 D) 3 32. Choose the bond below that is the strongest. A) C-F C) C-I B) C=O D) I-I E) C≡N 33. Which compound has the highest carbon-carbon bond strength? C) HCCH A) CH3CH3 D) all bond strengths are the same CH CH B) 2 2 34. Place the following in order of increasing bond length. NO2⁻ NO3⁻ NO A) NO < NO2⁻ < NO3⁻ B) NO2⁻ < NO3⁻ < NO D) NO < NO3⁻ < NO2⁻ E) NO3⁻ < NO2⁻ < NO C) NO3⁻ < NO < NO2⁻ 35. Rank the following molecules in decreasing bond energy. Cl2 Br2 F2 I2 I > Br > Cl > F A) 2 2 2 2 C) I2 > Cl2 > Br2 > F2 B) Cl2 > Br2 > F2 > I2 D) Cl2 > I2 > F2 > Br2 36. Which of the following processes are exothermic? A) Cl2(g) → 2Cl(g) B) Br(g) + e⁻ → Br⁻(g) C) Li(s) → Li(g) D) NaF(s) → Na⁺(g) + F⁻(g) E) None of the above are exothermic. 37. Which of the following processes are endothermic? A) the reaction associated with the lattice energy of LiCl. B) the reaction associated with the ionization energy of potassium. C) the reaction associated with the heat of formation of CaS. D) the formation of F2 from its elements in their standard states. E) None of the above are endothermic. 38. Use the bond energies provided to estimate ΔH°rxn for the reaction below. 2 Br2(l) + C2H2(g) → C2H2Br4(l) ΔH°rxn = ? Bond Bond Energy (kJ/mol) Br-Br 193 C≡C 837 C-C 347 C-Br 276 C-H 414 A) +407 kJ C) -228 kJ E) -648 kJ B) -324 kJ D) +573 kJ 4