4) Give the total number of electron domains and the hybridization for Xe in XeF 4. a) 6, sp 3 d 2 b) 4, sp 2 c) 5, sp 3 d d) 6, sp 3 e) 4, sp 3

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1 1) The hybridization that allows the formation of 2 π bonds from unhybridized p-orbitals is a) sp b) sp 2 c) sp 3 d) sp 3 d e) sp 3 d 2 2) Electrons in bonds may become delocalized between more than two atoms.. Electrons in bonds remain localized between two atoms a) sigma, pi b) sigma, sigma c) pi, sigma d) pi, pi e) ionic, sigma 3) An antibonding MO the corresponding bonding MO a) is always lower in energy than b) can accommodate more electrons than c) can accommodate fewer electrons than d) is always higher in energy than e) is always degenerate with 4) Give the total number of electron domains and the hybridization for Xe in XeF 4. a) 6, sp 3 d 2 b) 4, sp 2 c) 5, sp 3 d d) 6, sp 3 e) 4, sp 3 5) If a carbon-carbon bond contains two π bonds, it is classified as a bond. a) single b) double c) triple d) this is impossible for carbon e) carbon has no d-electrons so a bond will not form 6) CsCl crystallizes in a unit cell that contains the Cs + ion at the center of a cube that has a Cl ion at each corner. Each unit cell contains Cs + ion and Cl ion, respectively. a) 1, 8 b) 1, 1 c) 2, 1 d) 2, 2 e) 2, 4 7) The formula for bis(ethylenediamine)dihydroxomanganese (IV) chloride is. a) [Mn(OH) 2 (en) 3 ]Cl 3 b) [Mn(O) 2 (en)]cl c) [Mn(OH) 2 (en)]cl 2 d) [Mn(OH) 2 (en) 2 ]Cl 2 e) [Mg(OH) 2 (en) 2 ]Cl 3 8) The name of the compound [Ni(F) 2 (NH 3 )(H 2 O)](NO 3 ) 2 is a) difluorotriammineaquanickel(ii) nitrate b) difluoroammineaquanickel(iv) nitrate c) ammineaquadifluoronickel(iv) nitrate d) difluoroammineaquanickelate(iv) nitrate e) ammineaquadifluoronickelate(ii) nitrate 9) Ni in the complex ion [Ni(NH 3 ) 3 ] 2+ has d-electrons. a) 6 b) 3 c) 7 d) 4 e) 8 10) Ru forms octahedral complexes with CN = 6; one of its compounds contains Ru, 3 Cl, and 5 H 2 O. The addition of AgNO 3 solution to a solution of this complex results in the formation of 2 mol solid AgCl. Write the formula for the coordination compound, showing which ligands are likely to be present in the coordination sphere and which are not. a) [Ru(H 2 O) 5 ]Cl 3 b) [Ru(H 2 O) 5 Cl]Cl 2 c) [Ru(H 2 O)Cl 2 ]Cl 4H 2 O d) [Ru(Cl) 2 ]Cl 5H 2 O 11) Solutions of [Co(NH 3 ) 6 ] 2+, [Co(H 2 O) 6 ] 2+, and [Fe(SCN)] 2+ are colored. One is pink one is red and one is blue. Based on the spectrochemical series, the colors of [Co(NH 3 ) 6 ] 2+, [Co(H 2 O) 6 ] 2+, and [Fe(SCN)] 2+, in order, are. a) pink, red, blue b) red, pink, blue c) blue, pink, red

2 d) blue, red, pink e) red, blue, pink Questions consider the MO diagram below. σ* 1s σ 1s 12) The bond order for HeH is. a) 0 b) 0.5 c) 1 d) 1.5 e) 2 13) If an electron is moved from a lower to a higher energy orbital, the molecule must a) become more stable b) become as stable as H 2 c) not exist The diagram below shows two compounds, A and B; Use this diagram to answer questions A B σ* 2p π* 2p π 2p σ 2p σ* 2s σ 2s 14) The identities of A and B could reasonably be a) O 2 +, C 2 + b) NO, C 2 c) C 2 +, C 2 d) NO, OF + 15) Compound (A/B) is more paramagnetic and compound (A/B) has a longer bond a) A, A b) A,B c) B, B d) B, A 16) For the complexes [Cu(NO 2 ) 2 ] compared to [Cu(en) 2 ] 2+, the chelate effect predicts that a) [Cu(NO 2 ) 2 ] is more stable than [Cu(en) 2 ] 2+ b) [Cu(NO 2 ) 2 ] is less stable than [Cu(en) 2 ] 2+. c) [Cu(NO 2 ) 2 ] has the same stability as [Cu(en) 2 ] 2+ d) cannot predict without knowing the equilibrium constant e) cannot predict without knowing G 17) Why can NH 3 serve as a ligand but BH 3 cannot? a) B has no d-orbitals b) NH 3 is more abundant than BH 3 c) NH 3 is a gas d) B lacks a lone pair e) B is much smaller than N 18) The oxyhemoglobin molecule, with O 2 bound to iron, is a low-spin Fe(II) complex; it has unpaired d-electrons. The deoxyhemoglobin molecule, without the O 2 molecule is a high-spin Fe(II) complex; it has unpaired d-electrons. a) 0, 4 b) 2, 4 c) 4, 0 d) 4, 2 e) 0, 2 1

3 19-20) (Record this answer in two places (for both #19 and 20); this counts double credit 19) Bond angle 1 around N) is ; bond angle 2 (around C) is. H N C=O H H a) 90, 180 b) 109.5, 120 c) 120, 120 d) 109.5, e) 109.5, ) Record same answer as for # ) Record this answer in two places (for both #21 and 22); this counts double credit 21) Assume a metal atom can be represented as spheres as shown in the drawing below. If each atom has a radius of 1.24Å, the length of a side in the unit cell is Å. Exam 3B 14) The name of the compound [Ni(F) 2 (NH 3 )(H 2 O)](NO 3 ) 2 is a) difluorotriammineaquanickel(ii) nitrate b) difluoroammineaquanickel(iv) nitrate c) ammineaquadifluoronickel(iv) nitrate d) difluoroammineaquanickelate(iv) nitrate e) ammineaquadifluoronickelate(ii) nitrate 15) Ni in the complex ion [Ni(H 2 O) 4 ] 4+ has d-electrons. a) 6 b) 3 c) 7 d) 4 e) 8 16) Give the total number of electron domains and the hybridization for Xe in XeF 4. a) 4, sp 3 b) 4, sp 2 c) 5, sp 3 d d) 6, sp 3 e) 6, sp 3 d 2 17) If a carbon-carbon bond contains only one π bond, it is a bond. a) single b) double c) triple d) this is impossible for carbon e) carbon has no d-electrons so a bond will not form 18) Ru forms octahedral complexes with CN = 6; one of its compounds contains Ru, 4 Cl, and 5 H 2 O. The addition of AgNO 3 solution to a solution of this complex results in the formation of 3 mol solid AgCl. Write the formula for the coordination compound, showing which ligands are likely to be present in the coordination sphere and which are not. a) [Ru(H 2 O) 5 Cl]Cl 3 b) [Ru(H 2 O) 5 Cl 2 ]Cl 2 c) [Ru(H 2 O)Cl 3 ]Cl 4H 2 O d) [Ru(Cl)]Cl 3 5H 2 O 6-7) (Record this answer in two places (for both #6 and 7); this counts double credit) 6) Bond angle 1 (around N) is ; bond angle 2 (around C) is. H N C N H a) 90, 180 b) 109.5, 120 c) 120, 120 d) 109.5, e) 109.5, 180 7) Record same answer as for #6. 2

4 8) The hybridization that allows the formation of only 1 π bond from unhybridized p-orbitals is a) sp b) sp 2 c) sp 3 d) sp 3 d e) sp 3 d 2 9) Why can NH 3 serve as a ligand in a complex ion but BH 3 cannot? a) B has no d-orbitals b) NH 3 is more abundant than BH 3 c) NH 3 is a gas d) B lacks a lone pair e) B is much smaller than N 10) Electrons in bonds remain localized between two atoms. Electrons in bonds may become delocalized between more than two atoms. a) sigma, sigma b) sigma, pi c) pi, pi d) pi, sigma e) ionic, sigma 11) A bonding MO the corresponding antibonding MO a) is always lower in energy than b) can accommodate more electrons than c) can accommodate fewer electrons than d) is always higher in energy than e) is always degenerate with 12) Solutions of [Co(H 2 O) 6 ] 2+, [Fe(SCN)] 2+, and [Co(NH 3 ) 6 ] 2+ are colored. One is pink one is red and one is blue. Based on the spectrochemical series, the colors of [Co(H 2 O) 6 ] 2+, [Fe(SCN)] 2+, and [Co(NH 3 ) 6 ] 2+, in order, are. a) pink, blue, red b) red, blue, pink c) blue, pink, red d) blue, red, pink e) red, pink, blue Questions consider the MO diagram below. σ* 1s σ 1s 13) The bond order for HeH + is. a) 0 b) 1 c) 0.5 d) 1.5 e) 2 14) The ion HeH a) does not exist b) is more stable than HeH + c) is more stable than He 2 15) The absorbance spectrum (below) shows that the predominant color absorbed by this substance is and the color we would see when looking at the substance is. a) Yellow, violet b) Orange-red, blue-green c) Red, green d) Blue-green, orange-red e) Green, red Absorbance Wavelength, nm 3

5 The diagram below shows two compounds, A and B; Use this diagram to answer questions A B σ* 2p π* 2p π 2p σ 2p σ* 2s σ 2s 16) The identities of A and B could reasonably be a) O 2 +, C 2 + b) NO, C 2 c) C 2 +, C 2 d) NO, OF + 17) Compound (A/B) is less paramagnetic and compound (A/B) has a shorter bond a) A, A b) A,B c) B, B d) B, A 18) A compound crystallizes in a unit cell that contains the Rb + ion at the center of a cube that has a F ion at each corner. Each unit cell contains Rb + ion and F ion, respectively. a) 1, 8 b) 1, 1 c) 2, 1 d) 2, 2 e) 2, 4 19) The formula for bis(ethylenediamine)dihydroxomanganese (IV) chloride is. a) [Mn(OH) 2 (en) 3 ]Cl 3 b) [Mn(O) 2 (en)]cl c) [Mn(OH) 2 (en)]cl 2 d) [Mn(OH) 2 (en) 2 ]Cl 2 e) [Mg(OH) 2 (en) 2 ]Cl 3 20) For the complexes [Cu(NO 2 ) 2 ] compared to [Cu(en) 2 ] 2+, the chelate effect predicts that a) [Cu(NO 2 ) 2 ] is more stable than [Cu(en) 2 ] 2+ b) [Cu(NO 2 ) 2 ] has the same stability as [Cu(en) 2 ] 2+ c) [Cu(NO 2 ) 2 ] is less stable than [Cu(en) 2 ] 2+. d) cannot predict without knowing the equilibrium constant e) cannot predict without knowing G 21) The oxyhemoglobin molecule, with O 2 bound to iron, is a low-spin Fe(II) complex; it has unpaired d-electrons. The deoxyhemoglobin molecule, without the O 2 molecule is a high-spin Fe(II) complex; it has unpaired d-electrons. a) 0, 4 b) 2, 4 c) 4, 0 d) 4, 2 e) 0, ) Record this answer in two places (for both #22 and 23); this counts double credit. 22) Assume a metal atom can be represented as spheres as shown in the drawing below. If each atom has a radius of 1.78Å, the length of a side in the unit cell is Å. a) 1.80 b) 1.58 c) 1.89 d) 5.03 e) ) Record same answer as #22. 4