Tiêu đề 14. BIOMOLECULES.pdf ✅

(1.) The common molecular formula for disaccharide is [Page: 411] (a) C12H22O11 (b) C10H18O8 (c) C10H20O10 (d) C18H22O11 (2.) The monosaccharides are [Page: 412] (a) water insoluble (b) sour is taste (c) water soluble (d) bitter in taste. (3.) Commercially, glucose is obtained by [Page: 413] (a) Hydrolysis of sucrose by boiling it with H2SO4 at 393K (b) Hydrolysis of maltose by boiling it with H2SO4 at 373K (c) Hydrolysis of lactose by boiling it with H2SO4 at 373K (d) Hydrolysis of starch by boiling it with H2SO4 at 393K (4.) Which of the following reactions confirm the presence of straight chain of six carbon atoms in glucose? [Page: 413] (a) Reaction of glucose with hydroxylamine giving an oxime (b) Acetylation of glucose with acetic anhydride giving glucose penta-acetate (c) On prolonged heating with HI, it forms n-hexane (d) None of these (5.) Consider the following statements: [Page: 413] (I) Reaction of glucose with hydrogen cyanide confirms the presence of carbonyl group in glucose. (II) Oxidation of glucose with Br2/water and nitric acid gives gluconic acid. (III) Acetylation reaction of glucose confirms the presence of five OH group in glucose. Which of the following is/are correct? (a) I only (b) III only (c) I & II only (d) I & III only (6.) Which of the following statements is not true about glucose? [NCERT Exemplar Modified, Page: 414] (a) It does not give 2,4-DNP test. (b) Glucose is correctly named as D-(+)-glucose. (c) Oxidation of glucose and gluconic acid both with nitric acid gives saccharic acid. (d) It is present in furanose form.
(7.) Optical rotations of some compounds along with their structures are given below. Which of them have L-configuration? [NCERT Exemplar Modified, Page: 414] (a) I & II only (b) III only (c) I, II & III (d) none of these (8.) Glucose does not react with [Page: 415] (a) bromine water (b) hydroxylamine (c) sodium bisulphite (d) acetic anhydride. (9.) The a-D-glucose and b-D-glucose differ from each other due to difference in carbon atom with respect to its [Page: 415] (a) configuration at C-1 carbon (b) number of OH atoms (c) size of hemiacetal ring (d) conformation at C2 carbon. (10.) Glucose when treated with CH OH 3 in presence of dry HCl gas gives a- and b- methyl glucosides because it contains [Page: 415] (a) an aldehydic group (b) a CH2OH group (c) a ring structure (d) five OH group. (11.) When glucose is treated with acetic anhydride it forms penta-acetate which further does not react with hydroxyl amine group. [Page: 415] The above gives reaction confirms:
(a) presence of five OH group (b) presence of free CHO group (c) absence of free CHO group (d) Both (a) and (c). (12.) Which of the following reaction is not the proof of cyclic structure of glucose? [Page: 415] (a) Glucose does not give Schiff’s test. (b) The penta-acetate of glucose does not react with hydroxylamine. (c) Glucose reacts with acetic anhydride to form glucose penta-acetate. (d) Both (a) and (b). (13.) Which of the following pairs does not represent anomers? [NCERT Exemplar Modified, Page: 416]
(a) Only I (b) Only II (c) Only III (d) I & III both (14.) The correct corresponding order of names of four aldoses with configuration given below: [NEET Phase-II 2016, Page: 416] respectively, is (a) L-erythrose, L-threose, D-erythrose, D-threose (b) D-threose, D-erythrose, L-threose, L-erythrose (c) L-erythrose, L-threose, D-erythrose, D-threose (d) D-erythrose, D-threose, L-erythrose, L-threose (15.) Out of the given cyclic structures which pair represent an anomer? [NCERT Exemplar Modified, Page: 416]