| Beginning Problem #16
      4-bromoanisole 4-bromomethoxybenzene
   | Beginning Problem #17
      allyl alcohol 2-propenol
   | Beginning Problem #18
      3-nitrophenol   | 
  
    | Beginning Problem #19  2-phenylethanol   | Beginning Problem #20
      malonaldehyde bis(dimethyl acetal)   | Beginning Problem #21
      ethylbenzene   | 
  
    | Beginning Problem #22
      m-xylene 1,3-dimethylbenzene
   | Beginning Problem #23
      o-xylene 1,2-dimethylbenzene
   | Beginning Problem #24
      p-xylene 1,4-dimethylbenzene
   | 
  
    | Beginning Problem #25
      methyl ethyl ketone 2-butanone
   | Beginning Problem #26
      2-bromoanisole 1-bromo-2-methoxybenzene
   | Beginning Problem #27
      3-chloro-1-propanol   | 
  
    | Beginning Problem #28
      3-bromoanisole 1-bromo-3-methoxybenzene
   | Beginning Problem #29
      Anthranilic acid 2-aminobenzoic acid
   | Beginning Problem #30
      4-methoxycinnamaldehyde   |