1. Which is the most electronegative atom in the compound below? N H A) Carbon B) Nitrogen C) Oxygen D) Bromine Ans: C

Transcription

1 Chapter 1 1. Which is the most electronegative atom in the compound below? Br A) Carbon B) itrogen C) xygen D) Bromine 2. Which of the following correctly describes the electrons of a carbon atom in its ground state? A) 3 s electrons; 3 p electrons B) 2 1s electrons; 4 2p electrons C) 2 1s electrons; 2 2s electrons; 2 2p electrons D) 2 1s electrons; 2 2s electrons; 4 2p electrons E) one of these choices is correct. 3. Which of the following statements correctly describes the typical bonding of carbon, nitrogen, oxygen in organic molecules? A) Carbon participates in 4 covalent bonds, oxygen participates in 2 covalent bonds nitrogen participates in 5 covalent bonds. B) Carbon participates in 3 covalent bonds, oxygen participates in 2 covalent bonds nitrogen participates in 5 covalent bonds. C) Carbon participates in 4 covalent bonds, oxygen participates in 3 covalent bonds nitrogen participates in 3 covalent bonds. D) Carbon participates in 3 covalent bonds, oxygen participates in 3 covalent bonds nitrogen participates in 5 covalent bonds. E) Carbon participates in 4 covalent bonds, oxygen participates in 2 covalent bonds nitrogen participates in 3 covalent bonds. Ans: E 4. Which is not an acceptable Lewis structure for the anion (C 2 C)? a. b. C C C C A) a B) b C) c D) d c. C C d. C C Full file at Page 1

2 5. Which of the following is (are) valid Lewis structure(s) for the anion (CC 3 )? a. C C b. C C c. d. a b e. a, b, c C 6. Which of the following is (are) valid Lewis structure(s) for the anion (C 2 2 )? Assume the atoms are arranged as drawn. a. C b. C c. C d. a b e. a, b, c Ans: E 7. Which is the appropriate conversion of C 3 CClC 2 C(C 3 ) 2 to a skeletal formula? Cl a. b. c. d. Cl e. Cl Cl C 8. Convert the following compound from a condensed formula to a skeletal formula: C 3 C 2 C(C 3 ) 2 C 2 C(C 2 C 3 )C 2 C(C 3 ) 2. a. b. c. d. e. one of the choices is correct. Full file at Page 2

3 9. What is the condensed formula of the compound below? Br Br a. C 3 C 2 C(C 3 )C 2 C(C 3 )CBr 2 b. C 3 C 2 C 2 (C 3 )C 2 C(C 3 )CBr 2 c. C 3 C 2 C(C 3 )C(C 3 )C 2 CBr 2 A) a B) b C) c 10. Convert the following skeletal formula to a condensed formula. a. C 3 C 2 C(C 3 ) 2 C(C 2 C 3 )C(C 3 ) 2 b. C 3 C 2 C(C 3 )C(C 2 C 3 )C(C 3 ) 2 c. C 3 C(C 3 )C(C 2 C 3 )C(C 3 ) 2 A) a B) b C) c 11. Which of the following is not a valid Lewis structure of C 3 2? a. b. c. d. A) a B) b C) c D) d 2 Full file at Page 3

4 12. Which is not a valid resonance structure for the anion below? 2 C C 3 a. 2 C C 3 b. c. 2 C C 3 2 C C 3 d. 2 C C 3 e. All are valid resonance structures. 13. ow are the molecules in the following pair related? 3 C C 2 3 C C 2 A) They are constitutional isomers. C) They represent the same structure. 14. ow are the molecules in the following pair related? 3 C C C A) They are constitutional isomers. C) either of the choices is correct. 15. ow are the molecules in the following pair related? Cl A) Cl They are constitutional isomers. C) either of the choices is correct. 16. ow are the molecules in the following pair related? A) They are constitutional isomers. C) They are unrelated molecules. Full file at Page 4

5 17. ow are the molecules in the following pair related? 3 C 3 C A) They are constitutional isomers. C) either of the choices is correct. 18. ow are the molecules in the following pair related? A) They are constitutional isomers. C) either of the choices is correct. 19. ow are the molecules in the following pair related? A) They are constitutional isomers. C) either of the choices is correct. 20. ow are the molecules in the following pair related? 3 C C 3 3 C A) They are constitutional isomers. C) They are unrelated molecules. 21. ow are the molecules in the following pair related? 3 C C 3 A) They are constitutional isomers. C) either of the choices is correct. Full file at Page 5

6 22. Which is the most accurate representation of the resonance hybrid for the resonance structures shown below? δ δ a. δ b. δ δ c. δ d. δ δ δ δ δ δ e. one of the choices is correct. 23. Which of the following pairs of compounds are resonance structures? a. b. 3 C C 3 3 C C 2 c. C3 C 3 A) a B) b C) c 24. Which of the following structures are resonance structures of each other? a. b. c. A) a b B) b c C) a c D) All are resonance structures. E) one of these are resonance structures. Full file at Page 6

7 25. What is the hybridization for each of the indicated atoms in the following compound? 2 C C 3 a b c A) a - sp 2 ; b - sp 2 ; c - sp 2 C) a - sp; b - sp 2 ; c - sp 3 B) a - sp 2 ; b - sp 3 ; c - sp 3 D) a - sp 2 ; b - sp 2 ; c - sp Indicate the hybridization of the carbon ion in each compound below. C 3 C 3 a. b. A) a - sp 2 ; b - sp 2 B) a - sp 2 ; b - sp 3 C) a - sp 3 ; b - sp 3 D) a - sp 3 ; b - sp Consider the organic molecule drawn below. Describe which orbitals are used to form the C= bond. Since there are two bonds, you must identify two different sets of orbitals. A) C 2 sp 2 sp C s p D) C 3 sp 2 sp C p p B) C sp sp C p p E) C 2 sp 2 sp C 2p 2p C) C 2 sp 2 sp C s s Ans: E 28. Which of the following compounds has a labeled carbon atom that is sp 2 hybridized? C 3 a. 2 C C C 2 b. 3 C C 3 c. 3 C C 3 d. Compounds b c e. a, b c all have sp 3 hybridized carbon. Full file at Page 7

8 29. Which of the following compounds contains a labeled atom that is sp hybridized? (All nonbonded electron pairs have been drawn in.) a. C b. C c. C d. a b e. a, b c 30. Which of the compounds drawn below contains an sp 2 hybridized carbon atom? Select any all structures that apply. a. C 2 b. 2 C c. C + 3 d. C 3 A) a only B) b only C) d only D) a b E) b c Ans: E 31. Which of the labeled carbon atoms is (are) sp 2 hybridized? a. b. C + 3 c. 2 C C C 2 d. a b e. a, b c 32. Which statement best describes the orbital hybridization used to form bonds in the cation below? 2 C C A) The σ bond between the two carbon atoms is formed between two sp 2 hybridized atoms. B) The σ bond between the C is formed between an sp 2 hybridized C an sp hybridized. C) The σ bond between the two carbons is formed between one sp 3 hybridized C one sp hybridized C. D) The lone pair of electrons on is in an sp hybridized orbital. E) one of the statements is correct. Full file at Page 8

9 33. Indicate the formal charge on the B,, F atoms in the following compound. Cl Cl F B A) B: +1; : +1; F: 0 D) B: 1; : +1; F: 0 B) B: 1; : 1; F: 0 E) one of the choices is correct. C) B: +1; : 1; F: In the following compound, indicate the formal charge on all atoms except hydrogen. C A) Carbon +1; xygen +1; itrogen 2 D) Carbon +1; xygen 1; itrogen 1 B) Carbon 1; xygen +1; itrogen 2 E) one of the choices is correct. C) Carbon +1; xygen 1; itrogen In the following compound, indicate the formal charge on all atoms except hydrogen, from left to right. C C A) Carbon 0; itrogen 1; Carbon +1; xygen 0 B) Carbon 0; itrogen 1; Carbon 0; xygen 1 C) Carbon 0; itrogen 1; Carbon 0; xygen 1 D) Carbon 0; itrogen +1; Carbon 0; xygen 1 E) one of the choices is correct. 36. Which of the following compounds has a labeled atom with a +1 formal charge? (All nonbonded electron pairs have been drawn in.) a. 2 C b. C C 2 c. C C 2 d. C e. Full file at Page 9

10 37. Which of the following species has a labeled atom with a +1 formal charge? (All nonbonded electron pairs have been drawn in.) a. b. c. 2 C d. 3 C C C 3 e. 38. Which of the following species contains a carbon atom with a +1 formal charge? (All nonbonded electron pairs have been drawn in.) C 3 a. C C b. C C c. C C d. C e. C 3 C C 39. Which of the following species contains a carbon atom with a 1 formal charge? (All nonbonded electron pairs have been drawn in.) a. C C b. C C c. C d. C e. 2 C C C Which of the following species contains an atom with a +1 formal charge? (All nonbonded electron pairs have been drawn in.) a. b. c. d. e. 41. Which of the following species contains a carbon atom with a +1 formal charge? (All nonbonded electrons electron pairs have been drawn in.) C 3 C 2 a. C C b. C c. d. e. C C C C 3 3 C C Full file at Page 10

11 42. Which of the following species has (have) a trigonal planar structure with 120 bond angles around the labeled carbon atom? C 3 a. 2 C C C 2 b. 3 C C 3 c. 3 C C 3 d. b c e. a, b c 43. Which of the following molecules has (have) a trigonal planar geometry? a. b. c. d. a c e. one of the choices are correc 44. Which of the following compounds possess(es) a nitrogen with tetrahedral geometry? A) C 3 C : B) 2 C) + 4 D) C 3 C : 2 are both tetrahedral. E) are both tetrahedral. Ans: E 45. Which of the following molecules is (are) polar? a. C 3 Cl b. C 2 Cl 2 c. CCl 4 A) a B) b C) c D) a b E) b c 46. Which of the following statements is (are) correct? A) Ethane has sp 3 carbon atoms the geometry around each carbon is trigonal planar. B) Ethane has sp 3 carbon atoms the geometry around each carbon is tetrahedral. C) Ethane has sp 2 carbon atoms the geometry around each carbon is tetrahedral. D) Ethane has sp 2 carbon atoms the geometry around each carbon is trigonal planar. E) one of the statements are correct. Full file at Page 11

12 47. Which of the following statements is (are) correct? A) The carbon carbon distance in acetylene is longer than in ethylene. B) The carbon hydrogen bond in acetylene is weaker than the carbon hydrogen bond in ethane. C) The carbon carbon distance in acetylene is shorter than in ethane. D) The statements (The carbon carbon distance in acetylene is longer than in ethylene) (The carbon hydrogen bond in acetylene is weaker than the carbon hydrogen bond in ethane) are correct. E) The statements (The carbon hydrogen bond in acetylene is weaker than the carbon hydrogen bond in ethane) (The carbon carbon distance in acetylene is shorter than in ethane) are correct. 48. ow many hydrogens are directly bonded to each of the indicated carbon atoms? C a C c C b A) C a 1; C b 3; C c 2 D) C a 1; C b 3; C c 3 B) C a 2; C b 3; C c 2 E) one of the choices is correct. C) C a 1; C b 2; C c f the molecules listed, which does not have a dipole moment? A) Cl B) Cl 3 C) C D) BF 3 E) All molecules have a dipole moment. 50. For the elements Rb, F,, the order of increasing electronegativity is: A) Rb < F < D) F < Rb < B) Rb < < F E) The order cannot be determined. C) < F < Rb 51. Which of the following Lewis dot structure(s) below bear(s) a positive charge? a. Be b. c. B d. e. A) a B) b C) c D) c d E) d e Ans: E Full file at Page 12

13 52. Which of the following species has (have) a trigonal planar structure? a. C 3 b. C 3 c. 3 d. BF 3 e. 3 A) a, b, c D) b, d, e B) b d E) All of the choices are correct. C) d 53. What is the molecular shape of methyl anion? C 3 A) ctahedral D) Trigonal pyramidal B) Tetrahedral E) Linear C) Trigonal planar Challenge Questions 54. Enalapril is currently in clinical trials for congestive heart failure, its structure is given below. What is the correct molecular formula for this interesting antihypertensive agent? a. C d. C b. C e. C c. C Enalapril Full file at Page 13

14 55. The following compound is a synthetic intermediate in the production of lactacystin. Identify the orbital hybridization geometry of the atoms next to the three arrows. a Si C b c A) a sp 3 ; b sp 2 ; c sp 3 D) a sp 3 ; b sp 2 ; c sp B) a sp 2 ; b sp; c sp 3 E) one of the choices is correct. C) a sp 2 ; b sp 3 ; c sp The following scheme represents an S 1 mechanism for the conversion of alkyl halide a to ether b. Determine the correct structure for intermediate X based on the curved arrow formulism shown. I + I X a b a. b. c. d. e. Full file at Page 14

15 57. With reference to compound X drawn below, label each compound as an isomer, a resonance structure or neither. 2 X a. b. c. d. A) a. resonance structure; b. isomer; c. neither; d. isomer B) a. isomer; b. resonance structure; c. isomer; d. neither C) a. isomer; b. neither; c. isomer; d. resonance structure D) a. resonance structure; b. isomer; c. resonance structure; d. isomer E) one of the choices are correct. Use the following to answer questions 58-60: Answer the following questions about lidocaine, a commonly used dental anesthetic. a Lidocaine c 58. What orbitals are used to form the bond indicated by a? A) Csp 2 Csp 2 B) Csp 3 Csp 2 C) Csp 2 Csp D) Csp Csp 2 E) Csp 3 Csp 59. ow many carbon atoms have sp 2 hybridization? A) 7 B) 5 C) 6 D) 10 E) Predict the geometry around the oxygen atom indicated by arrow c. A) Linear D) Trigonal planar B) Tetrahedral E) Square planar C) Trigonal bipyrimidal Full file at Page 15