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MODEL PAPER 2025 — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 20251 Mark
MCQ
Assertion (A): Glucose does not form the hydrogensulphite addition product with NaHSO3.
Reason (R): Glucose exists in a six-membered cyclic structure called pyranose structure
  • A
    Both A and R are true and R is the correct explanation of A .
  • ✓
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

Correct option: B.
Both A and R are true but R is not the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A. Due to the absence of a free aldehydic group, it does not give a reaction with NaHSO3.

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