Exam 2 Form A Key 1 C 2 A 3 C 4 B 5 B 6 D 7 E 8 C 9 A 10 B 11 E 12 A 13 D 14 E 15 D 16 C 17 B 18 D 19 D 20 A 21 C 22 E 23 SP 1 2 18 14 2 a b H O Br SP 1 2 32 24 4 O B O c no yes d 1 1 33 e 2 3 f 0 1 g 109o 120o h bent trigonal planar i sp3 sp2 O For the next nine questions consider this molecule Note All atoms obey the octet rule Lone pairs have not been shown but must be considered when answering these questions H H O H H Cl C C H O C C C C 1 2 3 C N C C H 5 6 7 1 What is the bond angle at carbon 5 A 90o B 109o C 120o D 180o 2 What is the hybridization at carbon 7 C sp3 A sp B sp2 D sp4 3 What is the shape at carbon 4 A linear B bent C trigonal planar D 180o 5 What is the hybridization at carbon 3 C sp3 A sp B sp2 D sp4 6 What is the shape at nitrogen 9 A linear B bent C trigonal planar D 6 C N Cl H E tetrahedral D trigonal pyramidal E tetrahedral E 7 8 What is the bond order of the bond between carbon 3 and carbon 4 A 1 B 1 33 C 1 5 D 2 E 3 9 What is the bond order of the bond between carbon 8 and nitrogen 9 A 1 B 1 33 C 1 5 D 2 E 3 10 Which of the following represents a sigma bonding interaction A B C D H 9 8 D trigonal pyramidal 4 What is the bond angle at oxygen 1 A 90o B 109o C 120o 7 How many pi bonds exist in this molecule A 3 B 4 C 5 C H H 4 C E 11 What can you say about the polarity of H2O CH4 and SO2 A H2O is polar whereas CH4 and SO2 are not B H2O and CH4 are polar whereas SO2 is not C H2O CH4 and SO2 are all polar D SO2 is polar whereas H2O and CH4 are not E SO2 and H2O are polar whereas CH4 is not For the next two questions consider the following samples B 3 x 1023 Cl2 molecules C 3 mol of LiH A 2 mol F2 23 E 1 mol SiH4 D 6 x 10 HF molecules 12 Which sample contains the greatest mass 13 Which sample contains the least mass For the next two questions consider the following samples A 3 mol of SO2 B 2 mol of PCl3 C 1 mol of H2SO4 D 0 5 mol of C5H10O5 E 2 mol of H2Se 14 Which sample contains the least number of total atoms 15 Which sample contains the greatest number of total atoms 16 In drawing Lewis structures as we will do on the last page of this exam we follow the octet rule BUT if you were asked to critique the following two structures of SO2Cl2 neither of which follow the octet rule which would you say is better and why lone pairs not shown O 1 Cl S Cl 2 O Cl O S O Cl A Structure 1 is better because there are no formal charges on the O or Cl atoms B Structure 1 is better because the O and Cl atoms have formal charges C Structure 2 is better because there are no formal charges on the O or Cl atoms D Structure 2 is better because the O and Cl atoms have formal charges 17 Materials with high boiling points will also have A high vapor pressures and strong intermolecular forces B low vapor pressures and strong intermolecular forces C high vapor pressures and weak intermolecular forces D low vapor pressures and weak intermolecular forces 18 Comparing CO2 gas and Cl2 gas both at room temperature you would conclude A They have the same average kinetic energies and speeds B They have the same speed but CO2 has the greater average kinetic energy C They have the same speed but Cl2 has the greater average kinetic energy D They have the same average kinetic energy but CO2 has the greater speed E They have the same average kinetic energy but Cl2 has the greater speed 19 Assuming other factors stayed constant an increase in the temperature of a gas is consistent with A An increase in the pressure of the gas B An increase in the volume of the gas C A decrease in the number of moles of the gas D All of these E None of these 20 Select the correct statement A In a pi bonding interaction most of the electron density is between the nuclei but above and below the internuclear axis B In a sigma bonding interaction there is very little electron density between the nuclei C In a pi antibonding interaction most of the electron density is between the nuclei but above and below the internuclear axis D In a sigma antibonding interaction most of the electron density is between the nuclei along the internuclear axis 21 Consider the following three structures and select the accurate statement Note there is a negative formal charge shown on structure 3 O H H C H H C O H H H O C C 3 2 H H A Structure 1 has the longest CO bond and structure 3 has the strongest CO bond B Structure 3 has the shortest CO bond and structure 1 has the weakest CO bond C Structure 2 has the longest CO bond and structure 1 has the strongest CO bond D Structure 1 has the shortest CO bond and structure 3 has the weakest CO bond E Structure 3 has the longest CO bond and structure 2 has the strongest CO bond 1 22 Select the material with the highest boiling point A Cl2 B HCl C H2S D N2 E NH3 O 23 Answer the following questions for HOBr O is central and BO33 where all atoms obey the octet rule a 10 each Draw the Lewis structure for each species if resonance structures exist only draw one BO33 HOBr O is central b 4 each If you haven t done so already add formal charges to your structure The remaining parts of this question will be graded based on the structures you have drawn above c 2 each Yes or no do other resonance structures exist for HOBr BO33 d 2 each Based on your structure what is the OBr bond order in HOBr BO bond order in BO33 e 2 each How many sigma bonds are in HOBr BO33 f 2 each How many pi bonds are in HOBr BO33 BO33 g 4 each What is are the bond angle s in HOBr h 4 each Based on your structure what is the shape of …