Biomolecules HOTs Class 12 Chemistry

Please refer to Biomolecules HOTs Class 12 Chemistry provided below with solutions. All HOTs for Class 12 Chemistry with answers provided below have been designed as per the latest syllabus and examination petter issued by CBSE, NCERT, KVS. Students of Standard 12 Chemistry should learn the solved HOTS for Class 12 Chemistry provided below to gain better marks in examinations.

Biomolecules Class 12 Chemistry HOTs

Question. Isomerization of glucose produces
(a) galactose
(b) fructose
(c) mannose
(d) allose

Question. Biomolecules are
(a) aldehydes and ketones
(b) acids and esters
(c) carbohydrates, proteins and fats
(d) alcohols and phenols

Question. Which of the following is a disaccharide ?
(a) Lactose
(b) Starch
(c) Cellulose
(d) Fructose

Question. Invert sugar is
(a) chemically inactive form of sugar
(b) equimolecular mixture of glucose and fructose
(c) mixture of glucose and sucrose
(d) a variety of cane sugar

Question. The number of chiral carbon atoms present in cyclic structure α-D(+) glucose
(a) 3
(b) 4
(c) 5
(d) 6

Question. The α-D glucose and β-D glucose differ from each other due to difference in carbon atom with respect to its
(a) conformation
(b) configuration
(c) number of OH groups
(d) size of hemiacetal ring

Question. Which of the following carbohydrates are branched polymer of glucose?
(i) Amylose (ii) Amylopectin
(iii) Cellulose (iv) Glycogen
(a) (i) and (ii)
(b) (ii) and (iv)
(c) (iii) and (iv)
(d) (i), (ii) and (iii)

Question. Which of the following properties of glucose cannot be explained by its open chain structure?
(i) Glucose does not form hydrogen sulphite with NaHSO₃
(ii) On oxidation with HNO₃ glucose gives saccharic acid.
(iii) Glucose is found to exist in two different crystalline forms which are named as α and β.
(a) (ii) only
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (i) and (ii)

Question. Glucose is found to exist in two different α and β crystalline forms. These forms can be obtained by.
(i) The α form of glucose is obtained by crystallisation from concentrated solution of glucose at 303 K.
(ii) The β form of glucose is obtained by crystallisation from concentrated solution of glucose at 303 K.
(iii) The β form is obtained by crystallisation from hot and saturated aqueous solution at 371 K.
(iv) The α form is obtained by crystallisation from hot and saturated aqueous solution at 371 K.
(a) (i) and (iii)
(b) (ii) and (iv)
(c) (ii) and (iii)
(d) (i) only

Question.The two functional groups present in a typical carbohydrate are:
(a) – CHO and – COOH
(b) > C = O and – OH
(c) – OH and – CHO
(d) – OH and – COOH

Question. Maltose and glucose are
(a) oxidising sugar
(b) reducing sugar
(c) first is oxidising and second is reducing sugar
(d) both are non-reducing sugar

Question. The letter D and L in carbohydrates represent
(a) its optical rotation
(b) its mutarotation
(c) its direct synthesis
(d) its configuration

Question. Which is the least stable form of glucose ?
(a) α-D-Glucose
(b) β-D-Glucose
(c) Open chain structure
(d) All are equally stable

Question. Reduction of glucose by HI suggest that
(a) presence of OH groups
(b) presence of –CHO group
(c) cyclic structure of glucose
(d) six carbon atoms are arranged in straight chain

Question. The sugar present in fruits is
(a) fructose
(b) glucose
(c) sucrose
(d) galactose

Question. The function of glucose is to
(a) provides energy
(b) promote growth
(c) prevent diseases
(d) perform all above

Question. Which of the following is the sweetest sugar?
(a) Sucrose
(b) Glucose
(c) Fructose
(d) Maltose

Question. Which of the following reagent cannot distinguish between glucose and fructose?
(a) Fehling’s solution
(b) Tollen’s reagent
(c) Benedict’s solution
(d) All of these

Question. The presence or absence of hydroxyl group on which carbon atom of sugar differentiates RNA and DNA?
(a) 1st
(b) 2nd
(c) 3rd
(d) 4th

Question. The reaction of glucose with red P + HI is called
(a) Sandmeyer’s reaction
(b) Reformatsky reaction
(c) Gattermann’s reaction
(d) Reduction

Question. A carbohydrate insoluble in water is
(a) glucose
(b) fructose
(c) cellulose
(d) sucrose

Question. The pair of compounds in which both the compounds give positive test with Tollen’s reagent is
(a) Glucose and Sucrose
(b) Fructose and Sucrose
(c) Acetophenone and Hexanal
(d) Glucose and Fructose

Question. Reducing sugars reduce.
(a) only Fehling’s solution
(b) only Tollen’s solution.
(c) both (a) & (b)
(d) neither (a) nor (b)

Question. Lactose is made of
(a) α-D-glucose only
(b) α-D-glucose and β-D-glucose
(c) α-D-galactose and β-D-glucose
(d) β-D-galactose and β-D-glucose

Question. Which of the following monosaccharides are present as five membered cyclic structure (furanose structure)?
(i) Ribose
(ii) Glucose
(iii) Fructose
(iv) Galactose
(a) (i) and (ii)
(b) (i) and (iii)
(c) (iii) and (iv)
(d) (ii) and (iii)

Question. Which of the following statement is correct about fructose?
(a) It is dextrorotatory compound
(b) It exists in the two cyclic forms which is obtained by the addition of OH at C-5 to the >C=O group
(c) It exists as six membered ring
(d) It is named as furanose as it contain one oxygen and six carbon atom

Question. Which one of the following does not exhibit the phenomenon of mutarotation ?
(a) (+) – Sucrose
(b) (+) – Lactose
(c) (+) – Maltose
(d) (–) – Fructose

Question. Sucrose which is dextrorotatory in nature after hydrolysis gives glucose and fructose, among which
(i) Glucose is laevorotatory and fructose is dextrorotatory.
(ii) Glucose is dextrorotatory and fructose is laevorotatory
(iii) The mixture is laevorotatory.
(iv) Both are dextrorotatory.
(a) (i) and (iii)
(b) (ii) and (iii)
(b) (iii) and (iv)
(d) (iii) only

Question. Three cyclic structures of monosaccharides are given below which of these are anomers

Question. The sugar present in honey is
(a) sucrose
(b) glucose
(c) fructose
(d) maltose