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Biomolecules — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryBiomolecules3 Marks
Question
  1. Despite having an aldehyde group, glucose does not give 2,4-DNP test. What does this indicate?
  2. Draw the Haworth structure of a-D-(+)-Glucopyranose.
  3. What is the significance of D and (+) here?
✓

Answer

  1. This indicates that the aldehyde group in glucose is not free.
  2.  

  1. ‘D’ gives the configuration, i.e., the -OH group at C-5 is on the right hand side. (+) sign indicates that the isomer is dextrorotatory.

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