1) Based on the octet rule, magnesium most likely forms a ion. A) Mg- B) Mg6+ C) Mg2+ D) Mg6- E) Mg2-

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1 1) ased on the octet rule, magnesium most likely forms a ion. ) Mg- ) Mg6+ ) Mg2+ ) Mg6- E) Mg2-2) ased on the octet rule, phosphorus most likely forms a ion. ) P5- ) P5+ ) P+ ) P3- E) P3+ 3) Which ion below has a noble gas electron configuration? ) 2+ ) e2+ ) 2+ ) N2- E) Li2+ 4) The electron configuration of the phosphide ion (P3-) is. ) [Ne]3s23p3 ) [Ne]3s23p1 ) [Ne]3s2 ) [Ne]3p2 E) [Ne]3s23p6 5) The halogens, alkali metals, and alkaline earth metals have valence electrons, respectively. ) 8, 2, and 3 ) 7, 1, and 2 ) 2, 7, and 4 ) 2, 4, and 6 E) 1, 5, and 7 6) Lattice energy is. ) the sum of electron affinities of the components in an ionic solid ) the energy required to convert a mole of ionic solid into its constituent ions in the gas phase ) the sum of ionization energies of the components in an ionic solid ) the energy given off when gaseous ions combine to form one mole of an ionic solid E) the energy required to produce one mole of an ionic compound from its constituent elements in their standard states 7) In which of the molecules below is the carbon-carbon distance the shortest? ) H3-H3 ) H- -H ) H2hhH2 ) H3-H2-H3 E) H2hH2 8) Of the atoms below, is the most electronegative. ) a ) Rb ) S ) l E) Si 9) Electronegativit from left to right within a period and from top to bottom within group. ) increases, increases ) increases, decreases ) decreases, increases ) stays the same, increases E) increases, stays the same

2 10) The Lewis structure of sh 3 shows nonbonding electron pair(s) on s. ) 0 ) 1 ) 2 ) 3 E) This cannot be determined from the data given. 11) The Lewis structure of HN (H bonded to ) shows that has nonbonding electron pairs. ), 1 ) N, 2 ), 2 ) N, 1 E) H, 1 12) The Lewis structure of N H shows. 2 2 ) each nitrogen has one nonbinding electron pair ) each hydrogen has one nonbonding electron pair ) each nitrogen has two nonbinding electron pairs ) a nitrogen-nitrogen single bond E) a nitrogen-nitrogen triple bond onsider the following species when answering the questions that follow: (i) Pl (ii) H l (iii) HN (iv) H4 (v) NH3 13) In which Lewis structure does the central atom have a non-zero formal charge? ) (i) ) (ii) ) (iii) ) (v) E) none 14) The formal charge on carbon in the molecule below is. )0 )+1 )-1 )+3 E)+2 15) How many equivalent resonance forms can be drawn for SO without expanding octet on the sulfur atom (sulfur is the central atom)? 2 ) 3 ) 0 ) 4 ) 2 E) 1 For the questions that follow, consider the EST Lewis structures of the following oxyions: (iv) SO (v) ro (i) NO (ii) NO (iii) SO ) The central atoms in cannot expand octet. ) (i) only ) (ii) only ) (i) and (ii) ) (ii) and (iii) E) (iii) and (iv) 17) The Lewis structure of cannot be drawn without a non-zero formal charge on the central atom. ) (i) ) (ii) ) (iii) ) (iv) E) (v)

3 18) Lewis structures of which ions can be drawn with and without expanding the octet on the central atom? ) (i) and (ii) ) (iii) only ) (iv) only ) (iii) and (iv) E) (iii), (iv), and (v) 19) Lewis structures of which ions can be drawn with all formal charges being zero? ) all ) (i) and (ii) ) (ii) only ) (iii), (iv), and (v) E) none 20) The central atom in does not violate the octet rule. ) KrF ) Il - E) SF ) XeF ) F ). Refer to Molecular Orbital Theory. What is the molecular orbital configuration of N2? a. [core electrons] (σ2s) 2 (σ*2s) 2 (π2p) 2 (σ2p) 2 (σ*2p) 2 b. [core electrons] (σ2s) 2 (σ*2s) 2 (π2p) 2 (σ2p) 2 (π*2p) 2 c. [core electrons] (σ2s) 2 (σ*2s) 2 (π2p) 4 (σ2p) 2 d. [core electrons] (σ2s) 2 (σ*2s) 2 (π2p) 4 (σ2p) 2 (π*2p) 4 e. [core electrons] (σ2s) 2 (σ*2s) 2 (π2p) 4 (π*2p) 2 22) Using the table of average bond energies below, the H for the reaction is kj. H- -H (g) + H-I (g) H 2 hhi (g) ond: = H-I -I -H (kj/mol): ) +506 ) -506 ) -129 ) +129 E) ) s the number of covalent bonds between two atoms increases, the distance between the atoms and the strength of the bond between them. ) increases, increases ) decreases, decreases ) increases, decreases ) decreases, increases E) is unpredictable 24) ccording to VSEPR theor, if there are three electron domains in the valence shell of an atom, the will be arranged in a(n) geometry. ) trigonal bip ramidal ) tetrahedral ) linear ) octahedral E) trigonal planar

4 25) ccording to VSEPR theory, if there are five electron domains in the valence shell of an atom, they will be arranged in a(n) geometry. ) tetrahedral ) linear ) octahedral ) trigonal planar E) trigonal bipyramidal 26) The electron-domain geometry and molecular geometry of iodine trichloride are and, respectively. ) T-shaped, trigonal planar ) trigonal planar, trigonal planar ) trigonal bipyramidal, T-shaped ) tetrahedral, trigonal pyramidal E) octahedral, trigonal planar 27) The molecular geometry of is square planar. ) l4 ) XeF4 ) Il3 ) XeF2 E) PH3 28) The molecular geometry of the H O + ion is. 3 ) trigonal pyramidal ) octahedral ) bent ) tetrahedral E) linear 29) The molecular geometr of the S2 molecule is. ) tetrahedral ) T-shaped ) bent ) trigonal planar E) linear 30) The molecular geometry of the PF4 + ion is. ) trigonal bipyramidal ) tetrahedral ) trigonal pyramidal ) octahedral E) trigonal planar 31) Of the following species, will have bond angles of 120e. ) Nl3 ) l3 ) PH3 ) lf3 E) ll of these will have bond angles of 120e. 32) The molecular geometry of the ro ) T-shaped ) trigonal p ramidal ) tetrahedral ) ent E) trigonal planar 3 - ion is.

5 33) The molecular geometry of the left-most carbon atom in the molecule below is. ) octahedral ) tetrahedral ) trigonal planar ) T-shaped E) trigonal bipyramidal 34) The bond angles marked a, b, and c in the molecule below are about,, and, respectively. ) 120e, 120e, 90e ) 90e, 90e, 90e ) 120e, 120e, 109.5e ) 109.5e, 90e, 120e E) 109.5e, 120e, 109.5e 35) The central iodine atom in IF has unbonded electron pairs and bonded electron pairs 5 in its valence shell. ) 1, 4 ) 4, 1 ) 1, 5 ) 0, 5 E) 5, 1 36) Of the molecules below, only is polar. ) SbF 5 ) I 2 ) sh 3 ) SF 6 E) H 4 37) Of the molecules below, only is nonpolar. ) IF 3 ) rl 3 ) Pr 3 ) NF 3 E) F3 38) The molecular geometry of the HF molecule is, and the molecule is. 3 ) seesaw, nonpolar ) trigonal pyramidal, polar ) tetrahedral, nonpolar ) seesaw, polar E) tetrahedral, polar 39) The electron-domain geometr of a carbon-centered compound is tetrahedral. The h bridization of the central carbon atom is. ) sp3 ) sp ) sp3d ) sp 2 E) sp 3 d 40) The h bridization of the carbon atom in carbon dioxide is. ) sp3 d ) sp 2 ) sp ) sp3 E) sp3 d 2

6 41) The hybridization of the central atom in the XeF4 molecule is. ) sp2 ) sp3d 2 ) sp ) sp3d E) sp3 d 42) The sp3 d 2 atomic hybrid orbital set accommodates electron domains. ) 2 ) 3 ) 4 ) 5 E) 6 43) The hybridizations of iodine in IF 3 and IF are and, respectively. 5 ) sp 3, sp3d ) sp3d, sp 3 3d, sp 3 d 2 ) sp 3, sp 3 d 2 E) sp d 2 ) sp d 2, sp3 3 44) The blending of one s atomic orbital and two p atomic orbitals produces. ) two sp3 hybrid orbitals ) three sp2 hybrid orbitals ) two sp 2 hybrid orbitals ) three sp 3 hybrid orbitals E) three sp hybrid orbitals 45) The angles between sp 2 orbitals are. ) 109.5e ) 120e ) 180e ) 45e E) 90e 46) typical triple bond consists of. ) three ionic bonds ) three pi bonds ) three sigma bonds ) two sigma and one pi bond E) one sigma and two pi bonds 47) There is/are s bond(s) in the molecule below. ) 1 ) 2 ) 12 ) 13 E) 18 48) There is/are p bond(s) in the molecule below. ) 0 ) 1 ) 2 ) 4 E) 16

7 49. Which of the following is a correct Lewis structure for oxygen?.... E. 50. Which of the following is a correct Lewis structure for 2 H 6 O?.. nswers a and c are correct. E. nswers a, b, and c are correct Which Lewis structure is possible for N 2 O?.... E Which of the following is not a correct Lewis structure?. NO 2 -. NO 2. NO. N 2 O E. ll of the above are correct structures.

8 53. What is the correct Lewis structure of SF 4?.... E. 54. Which of the following are correct resonance structures of SO 3?. (1) and (5). (2) and (4). (1), (2), and (4). (2), (3) and (4) E. (1), (2), (4), and (5)

9 55. How many lone pairs of electrons are on the sulfur atom in sulfite ion, SO 2-3? E Formal charge is. the absolute value of the charge on a polyatomic anion or cation.. the difference between the number of lone pairs of electrons and shared pairs of electrons on any atom in a Lewis structure.. the difference between the number of valence electrons and the number of protons in any given atom.. equal to the number of valence electrons in a free atom minus the number of shared in covalent bonds. E. the difference between the number of valence electrons in a free atom and the number of electrons assigned to the atom in a Lewis structure. 57. What is the formal charge on each atom in dichloromethane, H 2 l 2?. = 0, H = 0, l = 0. = 0, H = -1, l = +1. = 0, H = +1, l = -1. = -2, H = +1, l = +1 E. = +4, H = -1, l = Using formal charges and the octet rule, determine which Lewis structure of ON - is most stable. a. b. c. d. e. 59. Use VSEPR theory to predict the molecular geometry of H 3.. triangular planar. triangular pyramidal. linear. tetrahedral E. triangular bipyramidal 60. Use VSEPR theory to predict the molecular geometry of Il 3.. triangular planar. triangular pyramidal. triangular bipyramidal. t-shaped E. octahedral 61. Which of the following species have the same molecular geometry: O 2, H 2 O, el 2, and N 2 O?. O 2 and N 2 O only. H 2 O and N 2 O only. H 2 O and el 2 only. O 2 and el 2 only E. O 2, el 2, and N 2 O

10 62. What are the bond angles in SF 6?. 90º and 180º º. 120º. 90º and 120º E. 180º 63. What is the hybridization of the carbon atoms in benzene, 6 H 6?. sp. sp 2. sp 3. sp 3 d E. sp 3 d What hybridization change does the carbon atom undergo in the combustion of methane? H 4 (g) + 2O 2 (g) O 2 (g) + 2H 2 O(g). sp sp 2. sp 2 sp 3. sp 3 sp. sp 2 sp E. none 65. How many sigma and pi bonds are present in the following molecule?. 8 sigma bonds and 1 pi bond. 8 sigma bonds and 2 pi bonds. 10 sigma bonds and 2 pi bonds. 11 sigma bonds and 2 pi bonds E. 11 sigma bonds and 1 pi bond 66. Which element is the most electronegative?. phosphorus. silicon. carbon. nitrogen E. oxygen 67. Which of the following compounds is expected to have the strongest ionic bonds?. RbF. NaF. NaI. sr E. si 68. The central atom in XeF 4 is surrounded by. 3 single bonds, 1 double bond, and no lone pairs of electrons.. 2 single bonds, 2 double bonds, and no lone pairs of electrons.. 3 single bonds, 1 double bond, and 1 lone pair of electrons.. 4 single bonds, no double bonds, and no lone pairs of electrons. E. 4 single bonds, no double bonds, and 2 lone pairs of electrons. 69. Which one of the following molecules has a dipole moment?. I 4. PF 5. Nl 3. SO 3 E. O 2

11 70. Label the hybridization at #1, #2, #3, and #4 in the molecule a. sp sp sp 3 sp 3 d b. sp sp sp 2 sp 3 c. sp sp 2 sp 2 sp 2 d. sp 2 sp 2 sp 3 sp 3 e. sp 3 sp 3 sp 3 sp Which molecule is polar?. F 3. H 2 Se. N 2. GeF 4 E. O London forces exist. for all molecules.. only for molecules with nonpolar bonds.. only for molecules with polar bonds.. only for molecules with metallic bonds. E. only for molecules with hydrogen bonding. 73. Which of the following interactions are present between O 2 molecules? I. London forces II. ion-dipole forces III. hydrogen bonding IV. dipole-dipole attractions. I only. II and III. II only. III only E. Iand IV 74. How many sigma (σ) bonds and pi (π) bonds are in the following molecule?. five σ and two π. five σ and three π. five σ and five π. seven σ and two π E. seven σ and three π 75. Which of the following characteristics apply to Pl 3? 1. nonpolar molecule 2. polar bonds 3. trigonal-pyramidal molecular geometry 4. sp 2 hybridized. 1 and 2. 2 and 3. 3 and 4. 1, 2, and 3 E. 1, 2, 3, and Which of the underlined atoms (1, 2, N, and O) are sp2 hybridized?. 1 and 2. 1, N, and O. N and O. O and 2 E. O only

12 Molecular Orbital Theory The following molecular orbital diagram may be used for the following problems. For oxygen and fluorine, the σ 2p orbital should be lower in energy than the π 2p. However, the diagram will still yield correct bond order and magnetic behavior for these molecules. 77.ccording to molecular orbital theory, which of the following species is the most likely to exist? 2- a. H 2 b. He 2 c. Li 2 d. Li 2 e. e ccording to molecular orbital theory, what is the bond order of nitrogen, N2?. 1. 3/ /2 E Use molecular orbital theory to predict which species is paramagnetic.. N2. O2. F2. Li2 E. H2 80. Which one of the following best defines the word allotropes? ifferent structural forms of an element pair of substances that differ by H + Elements that possess properties intermediate between those of metals and nonmetals toms of a given atomic number that have a specific number of neutrons E The different phases (solid, liquid or gas) of a substance

13 81. How many electrons are there in the valence shell of the O 2 ion? E What is the formula of the compound formed between magnesium and oxygen? MgO Mg2O2 Mg2O3 MgO2 E Mg2O 83. Which one of the following statements concerning elements in the Periodic Table is correct? E Elements of the same group all have the same number of electrons in the outermost occupied electron shell. Elements of Group 16 occur as cations in ionic compounds. Oxides of elements in Groups 16 and 17 are basic. The halogens (Group 17) are all gases at room temperature. The Group 13 elements are all metals Rn is unstable and decays by losing 6 neutrons and 2 protons. What is the final decay product? E i 216 i 216 Pb 214 Po 212 Tl 85. Which one of the following species has the least number of electrons? 35 l 17 E 39 r r a l

14 86. Which one of the following pairs are isotopes? O 2 and O l and l I 2 (g) and I 2 (s) Mg 2+ and Ne E F + and F 87. Which one of the following describes the major intermolecular force in I2(s)? covalent bonds ionic bonds hydrogen bonds dispersion forces E dipole-dipole forces 88. How many protons (p), neutrons (n) and electrons (e) are present in p 80 n 198 e 80 p 120 n 78 e 120 p 80 n 118 e 80 p 200 n 78 e E 120 p 200 n 118 e 80 Hg2+? 89. Which symbol correctly represents an isotope with 14 protons and 15 neutrons? 15 Si P 30 P Si 14 E P 90. How many bonding and non-bonding electron pairs are found in the F3 molecule? 1 bonding and 3 non-bonding 2 bonding and 2 non-bonding 3 bonding and 0 non-bonding 3 bonding and 1 non-bonding E 4 bonding and 0 non-bonding 91. Which one of the following pairs of atoms would form a non-polar covalent bond? and O N and O l and l Na and l E Ne and Ne 92. Which one of the following species has the same electron configuration as the l 3+ cation? F l S 2 O E Mg +

15 93. Which one of the following elements has valence electrons in the n = 3 shell? beryllium oxygen silicon neon E hydrogen 94. Which one of the following species contains a polar covalent bond? oxygen carbon dioxide sodium chloride magnesium fluoride E helium 95. Which one of the following structures represents a 2p z atomic orbital?. z. z z. y y y x x x z. E. z y y x x 96. What is the oxidation number of phosphorus in KH 2 PO 4? VI II 0 +V E +VI

16 97. Which force is most important in allowing ammonia, NH 3, to dissolve in water? E hydrogen bonding dipole-induced dipole ion-dipole dipole-dipole ionic 98. Which one of the following substances will form strong hydrogen bonds? HOOH H 3 N l 4 SiH 4 E H 3 OH Which one of the following statements regarding a catalyst is not correct? n enzyme is a catalyst that only binds certain substrates. n enzyme is a protein that is a highly efficient catalyst for one or more chemical reactions in a living system. atalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy. atalysts do not alter the equilibrium constant for a chemical reaction Which one of the following statements is not correct? Since voltage depends on concentrations, using standard conditions makes it easier to compare different electrochemical reactions. We have to measure the cell potential to obtain the difference in potential energy because the potential of half-reactions cannot be measured directly. The direction of a redox reaction can only be determined experimentally. Half-cell potentials for half-reactions are determined by combining the relevant half-cell with a standardised half-cell.

17 nswer Key 3) 4) E 5) 41) 42) E 43) 44) 47) 9) 48) 10) E E E 66. E E ) E 14) 15) 16) 17) 18) E 19) E 20) ) 23) 24) E 25) E 26) 27) 28) 29) E 30) 31) 32) om 33) 34) E 35) 36) 37) E 38) E 39) 40) 93 re.c 46) E 92 kaa 7) 8) 91 bio 45) 90 w.i 6) 11) 12) E E 79. ww 1) 2) 99