Unit 4 Exam

Unit 4 Exam-2011 Form A Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Of the bonds C-N, C-N, and CN, the C-N bond is A) strongest/shortest B) strongest/longest C) weakest/shortest D) weakest/longest E) intermediate in both strength and length 2) The hybridization of the oxygen atom labeled y in the structure below is The C-O-H bond angle is H H:0:x ↑ H A) sp, 180° B) sp2, 109.5" C) sp³, 104.5 D) sp3d2, 90° E) sp. 90° 3) A triatomic molecule cannot be linear if the hybridization of the central atoms is A) sp B) sp2 C) sp3 D) sp² or sp³ E) sp²d or sp3d2 4) In the nitrite ion (NO2-), A) both bonds are single bonds B) both bonds are double bonds C) one bond is a double bond and the other is a single bond D) both bonds are the same, each being stronger and shorter than a single bond but longer and weaker than a double bond E) there are 20 valence electrons 5) The bond angles marked a, b, and c in the molecule below are about, respectively. and 10: Η:0: H-NCCC-O-н bc a a H H A) 90, 90, 90 B) 120, 120°, 90° C) 109.5, 120, 109.5" D) 107", 120, 109.5" E) 109.5", 90, 120° 6) The hybridization of the central atom in the XeF4 molecule is, A) sp B) sp2 C) sp3 D) sp³d E) sp3d2 Consider the following species when answering the questions that follow: (1) PC13 (ii) CH2Cl2 (iii) HCN (iv) C2H4 (v) NH3 7) The Lewis structures of hydrogen. have to have multiple bonds in order to satisfy octet on all atoms other than A) (i) and (v) B) (ii) and (v) C) (iii) only D) (iii) and (iv) E) (iv) only 8) In the Lewis structures of the central atom has one lone pair of electrons. A) (1) only B) (i) and (iii) C) (i) and (iv) D) (i) and (v) E) (ii) and (iv) 9) In order to exhibit delocalized a bonding, a molecule must have, A) at least two a bonds B) at least two resonance structures C) at least three a bonds D) at least four atoms E) trigonal planar electron domain geometry 10) The electron-domain geometry of is tetrahedral. A) CBr B) PH3 C) CCl2Br2 D) XeF4 E) all of the above except XeF4 11) For a given arrangement of ions, the lattice energy increases as ionic radius and as ionic charge A) decreases, increases B) increases, decreases C) increases, increases D) decreases, decreases E) This cannot be predicted. 12) How many different resonance structures can be drawn for the molecule of SO3 without having to violate the octet rule on the sulfur atom? A) 5 B) 2 C) 1 D) 4 E) 3 Consider the following species when answering the following questions: (i) PC13 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6 13) Which molecules are polar? A) (1) and (ii) B) (i) and (iii) C) (ii) and (iii) D) (iii) and (iv) E) (iv) and (v) 14) Which of the following has the bonds correctly arranged in order of increasing polarity? A) Be-F, Mg-F, N-F, O-F B) O-F, N-F, Be-F, Mg-F C) O-F, Be-F, Mg-F, N-F D) N-F, Be-F, Mg-F, O-F E) Mg-F, Be-F, N-F, O-F 15) Using the table of average bond energies below, the AH for the reaction is, kJ. CO (g) + 2H2 (g) H3C-O-H (g) Bond: D(kJ/mol): C-O 358 CHO 799 CO C-H H-HO-H 463 A) +276 B)-276 1072 413 436 C) +735 D)-735 E)-116 Answer Key Testame: UNIT 4 TEST-2011 FORM A. TST MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) D 2) C 3) D 4) D 5) D 6) В 7) D 8) D