Question

Which of the following statements support the cyclic form for glucose?
(i) It doesn't give Schiffs test.
(ii) It is found to exist in two different crystalline forms
(iii) It oxidizes with nitric acid to give saccharic acid
(iv) Pentaacetate of glucose doesn't react with hydroxylamine

• A. (i), (ii) and (iv) only
• B. (i), (iii) and (iv) only
• C. (ii) and (iii) only
• D. (i), (ii) and (iii) only

Answer 1

Answer: (A)

(ii) Anomeric crystalline form
(i) do not give Schiff's test, because, $-CHO$ group is not free.
(iv) Pentaacetate do not react with hydroxylamine, because $⟩C=0$ is not available.
So, statements (i), (ii) and (iv) support the cyclic structure of glucose.