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19 Nov 2019
Please help ! 1. Which of the following functional group exhibits the lowest stretching vibration frequency? A) sp C-H B). sp2 C-H C) sp3 C-D D) sp? C-D 2. Estimate the chemical shift value of the protons labeled with on the basis ofknown H chemical shift values shown below 2.0 1.0 O2N-CH2-CH2-CH3 3. Which of the followings is the most reactive one in electrophilic aromatic substitution NH, 4. If a proton resonance at 200 MHz in a spectrometer with a magnetic field of 4.7 T, the resonance frequency in a spectrometer with a magnetic field of 9.4 Tis 5. In which of following compounds carbon-hydrogen bond shows the highest stretching vibration frequency in its IR spectrum? A. Ethane B. Ethene C. Ethyne D. Methane 6. Draw the bond-line formula of the hydrocarbon that has the longest max with the molecular formula of C6H8 7. Which of following statements about electrophilic aromatic substitution (EAS) mechanism is correct? A EAS follows SN2 mechansim B. EAS follows SN1 mechanism C. In an EAS reaction, an elimination step follows an electrophilic addition step D.Ina EAS reaction, an electronphilic addition follows an elimination step 8. The chemical shift of one proton is 6.5 ppm on a 200 MHz spectrometer, its chemical shift on a 400 spectrometer is 9. 13C NMR offers better but poorer than IHNMR 10. The electrophile in the following Friedel-Crafts acylation reaction is Ca Lewis structure).
Please help !
1. Which of the following functional group exhibits the lowest stretching vibration frequency? A) sp C-H B). sp2 C-H C) sp3 C-D D) sp? C-D 2. Estimate the chemical shift value of the protons labeled with on the basis ofknown H chemical shift values shown below 2.0 1.0 O2N-CH2-CH2-CH3 3. Which of the followings is the most reactive one in electrophilic aromatic substitution NH, 4. If a proton resonance at 200 MHz in a spectrometer with a magnetic field of 4.7 T, the resonance frequency in a spectrometer with a magnetic field of 9.4 Tis 5. In which of following compounds carbon-hydrogen bond shows the highest stretching vibration frequency in its IR spectrum? A. Ethane B. Ethene C. Ethyne D. Methane 6. Draw the bond-line formula of the hydrocarbon that has the longest max with the molecular formula of C6H8 7. Which of following statements about electrophilic aromatic substitution (EAS) mechanism is correct? A EAS follows SN2 mechansim B. EAS follows SN1 mechanism C. In an EAS reaction, an elimination step follows an electrophilic addition step D.Ina EAS reaction, an electronphilic addition follows an elimination step 8. The chemical shift of one proton is 6.5 ppm on a 200 MHz spectrometer, its chemical shift on a 400 spectrometer is 9. 13C NMR offers better but poorer than IHNMR 10. The electrophile in the following Friedel-Crafts acylation reaction is Ca Lewis structure).
Jarrod RobelLv2
30 Mar 2019