Part A. Please circle the best answer. (3 pts each) 1. In which region would you look for C-H stretching modes? a. 2300-2200cm c. 3300-2700cm b. 1700-1600cm d. 1800-1600cm 2. Which type of radiation is used in nuclear magnetic resonance a. infra-red light b. ultraviolet light c. radio waves d visible light 3. Which area of the IR spectrum is called the "finger print region"? b. 2800-2000cm a. 4000-2800cm c. 2000-1400cm 4. Which one of the following alkenes does not show any IR band for the symmetric C-C (triple) bond stretch? a. 1-pentyne b. 2-pentyne c. 1-butyne d. 2-butyne 5. What is the mass of the "molecular ion (parent ion)" M generated from methylcyclohexane? a. 83 b. 96 c. 98 d. 100 6. Consider the structure isomers, 1-bromopropane (A) and 2-bromo- propane (B), respectively. How many unique proton peaks are in its 'H NMR? b. A: 3 types, B: 2 types d. A: 8 types, B: 8 types a. A: 4 types, B: 4 types c. A: 2 types, B: 3 types 7. Consider the C NMR spectrum of propan-2-ol. How many signals would you expect in the broadband decoupled carbon-13 spectrum of this molecule? a. b. 2 C. d. 4 8. In what region of the 'H-NMR spectrum would you expect to have a signal for the -CH2- (methylene group) of diethyl ether, CH,CH,OCH,CH? a. 0-2 ppnm ppm b. 3-4 ppm d. 7-8 c. 5-6 ppmm 9. How many doublets are from propan-2-ol in t he 'H NMR? C.