Determine the nature of the conjugated pi electron

Question

1. Select the most reasonable formula for the compound with the following mass spectral data:

• M⁺ m/z = 136 and M⁺ atm/z = 138 of approximately equal intensity
  C₄H₉Br
• C₆₁₃OCl
• C₉H₁₂O
  C₁₀H₁₆

2. Which of the following does not involve the interaction of molecules with the electromagnetic energy?

• nuclear magnetic resonance spectroscopy
• infrared spectroscopy mass spectrometry
• ultraviolet spectroscopy

3. The amount of energy in infrared light corresponds to:

• the amount of energy needed to "flip" the spin of a ¹³C or ¹H nucleus
• the amount of energy needed to promote one electron from a bonding to an anti bonding molecular orbital
• the amount of energy needed to increase certain molecular motions, such as bond vibrations, in organic molecules
• the amount of energy needed to strip a molecule of one electron to generate a cation radical

4. Examining the infrared spectrum of a compound allows us to:

• determine the nature of the conjugated pi electron system in the compound
• determine the carbon-hydrogen framework of the compound
• determine the types of functional groups present in the compound
• determine the molecular weight of the compound