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Amines — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryAmines3 Marks
Question
Account for any two of the following:
  1. Amines are basic substances while amides are neutral.
  2. Nitro compounds have higher boiling points than the hydrocarbons having almost the same molecular mass.
  3. Aromatic amines are weaker bases than aliphatic amines.
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Answer

  1. Due to the presence of lone pair of electrons on nitrogen of amines they are basic in nature whereas nitrogen of amides acquire positive charge due to resonance with carbonyl group which makes it neutral. 
  2. Because of the polar nature of nitro compounds leading to stronger interactions due to dipole-dipole interactions.
  3. Due to resonance in aromatic amines nitrogen acquires positive charge which decreases its basic character whereas there is no resonance in aliphatic amines.

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