Chem 260/261 First Exam 2/12/01 Sample 1Name: Score: This exam consists of 14 multiple choice questions worth 3 pts each, 3 short answer questionsworth 10 pts each, and 2 problems worth 14 pts each. BUDGET YOUR TIME WISELY. Thisexam has 13 pages including the cover page, nine pages of questions, two information sheets anda blank scratch sheet.Multiple Choice Answers:1. 5. 9. 13.2. 6. 10. 14.3. 7. 11.4. 8. 12.SCORE: Indicate the Letters for Questions 15 and 16 below.Scores:1-14. /4215. ( ) /1015. ( ) /1015. ( ) /1016. ( ) /1416. ( ) /14Total: /100Name Chem 260/261 First Exam 2/12/01 Sample 2Multiple Choice (42 pts): 14 questions. Choose the letter corresponding to the best single answerfor each question. Put your answers in the numbered boxes on the cover sheet of this exam.SAMPLE QUESTIONS:1.) How many rotational degrees of freedom does butane possess?(a) 2 (b) 3 (c) 5 (d) 14(e) 42 (f) 36 (g) 37 (h) 12.) In which spectral region would you expect to observe valence electronic transitions?(a) γ-ray (b) X-ray (c) UV (d) Visible(e) Infrared (f) Microwave (g) Radio frequency 3.) Which of the following forces are shortest range?(a) Dipole-Dipole Forces (b) Repulsive forces(c) London Dispersion Forces (d) Coulomb ForcesName Chem 260/261 First Exam 2/12/01 Sample 315.) Short Answer (30 points): In the space available answer 3 of the following 5 questions. Indicate the questions you want graded on the cover sheet. Use complete sentences! Correctanswers expressed in poor grammar will be docked 1 point. Use equations and diagrams wherehelpful or required. Each question is worth 10 points.SAMPLE QUESTIONS:A.) Consider a molecular orbital picture of MgH. If MgH is ionized to form MgH+ what changesdo you expect in the bond length and the vibrational frequency? Why?B.) Describe hydrogen bonding and explain why it is an important and unique interaction,contrasting it with other Van der Waals interactions. Give two examples illustrating theimportance of hydrogen bonding.Name Chem 260/261 First Exam 2/12/01 Sample 416.) (28 pts): In the space available solve 2 of the following 3 problems. Indicate the questionsyou want graded on the cover sheet. Partial credit will be given for work shown in the indicatedarea only. You must show how the correct answer was obtained or no credit will be given. Eachproblem is worth 14 points.SAMPLE PROBLEM:B.) The J = 0 to 2 rotational transition of HD is observed in the Raman spectrum at 273.93 cm-1. (i) Based on this observation what is the bond length in the HD molecule? (ii) Would you expect to observe the J = 0 to J = 2 transition of H2 above or below 273.93 cm-1 ? Explain your answer.hν  Φ  mv22 λ  hmvEvib/rothc  ν n12 BJ(J1) xν n122 D J(J1)2 α n12J(J1)ν  12πkµ B  h8π2cI  h8π2c µr2eA  … cl ψn  2LsinnπLx En  n2h28mL2Possibly Useful Constants and Quantities and Equations:Constant or Quantity SI unitsAvogadro's Number (No) 6.02214×1023 mol-1Boltzmann's Constant (k) 1.38066×10-23 J K-1Electron Charge (e) 1.602177×10-19 CElectron Mass (me) 9.10939×10-31 kgGas Constant (R) 8.31451 J K-1 mol-1Planck Constant (h) 6.62608×10-34 J sProton Mass (mp) 1.67262×10-27 kgRydberg Constant (R) 1.09677×105 cm-1Speed of Light in a Vacuum (c) 2.99792458×108 m s-1Atomic Mass Unit 1.66054×10-27 kgBohr Radius (ao) 5.29177×10-11 mAtomic Weight of Hydrogen (1H) 1.007825 amuAW of Deuterium (2D) 2.014 amuPhotoelectric Effect: De Broglie Wavelength:Energy Levels:Vibrational Frequency and Rotational Constant:Beer's Law: The Particle in a Box, n = 1,2,3,...:Interaction energies:Type of Interaction Energy of InteractionCovalent Bond No simple ExpressionIon-Ion e2/…rIon-Dipole κeµ/…r2κ is geometry dependent.Dipole-Dipole κµAµB/…r3κ is geometry dependent.Ion-Induced Dipole αe2/2…r4Dipole-Induced Dipole αµ2/…r6Dispersion 3Iα2/4r6Hydrogen Bond No Simple