Description : Claisen condensation gives__________ a) Hydroxyl compound b) β- keto ester c) Γ- diketone d) Α-diketone
Last Answer : b) β- keto ester
Description : Fatty acids are (a) Unsaturated dicarboxylic acids (b) Long-chain alkanoic acids (c) Aromatic carboxylic acids (d) Aromatic dicarboxylic acids
Last Answer : Long-chain alkanoic acids
Description : When carboxylic acids and dicarboxylic acids have similar molecular weights, how do their melting points compare? (a) Carboxylic acids have greater melting points. (b) Dicarboxylic acids have greater melting points. (c) Both acids have similar melting points. (d) No consistent trend exists
Last Answer : Dicarboxylic acids have greater melting points
Description : Which of the following statements is correct for a saturated alkyl halide? (a) the C-X bond results from overlap of the s orbital of carbon and the p orbital of the halogen (X) (b) the C-X bond ... the C-X bond results from overlap of the sp2 orbital of carbon and the p orbital of the halogen (X)
Last Answer : the C–X bond results from overlap of the sp3 orbital of carbon and the p orbital of the halogen (X)
Description : Which reaction does not yield an ester as one of the products? (a) A carboxylic acid is heated with an alcohol (b) A Grignard reagent is added to a carboxylic acid (c) An acid halide is treated with an alcohol (d) An alkyl halide is heated with the salt of a carboxylic acid
Last Answer : A Grignard reagent is added to a carboxylic acid
Description : The greater acidity of carboxylic acids compared to alcohols arises primarily from : (a) the electron-donating effect of the hydroxyl group (b) the electron-withdrawing effect of the carboxyl ... of α-hydrogens of carboxylic acids (d) the resonance stability associated with the carboxylate ion
Last Answer : the resonance stability associated with the carboxylate ion
Description : An inorganic halide `(A)` reacts with water to form two acids `(B)` and `(c). (A)` also reacts with `NaOH` to form two salts `(D)` and `( E)` which re
Last Answer : An inorganic halide `(A)` reacts with water to form two acids `(B)` and `(c). (A)` also reacts with `NaOH` to ... . `SF_(6)` C. `SeF_(6)` D. `SF_(4)`
Description : The mutarotation of glucose is characterized by : (a) a change from an aldehyde to ketone structure. (b) a change of specific rotation from a (+) to a (–) value. (c) the presence of an intramolecular bridge structure. (d) the irreversible change from α-D to the β-D form.
Last Answer : the presence of an intramolecular bridge structure.
Description : Give an example of oxidation of halide by another halogen. Explain the feasibility of the reaction.
Last Answer : Give an example of oxidation of halide by another halogen. Explain the feasibility of the reaction.
Description : Which of the following will not displace the halogen from the solution of the halide?
Last Answer : Which of the following will not displace the halogen from the solution of the halide? A. `Br_2` added to ... F_2` added to KCl D. `Cl_2` added to NaF
Description : `P` and `Q` are isomers of dicarboxylic acid `C_(4)H_(4)O_(4)`. Bothdecolorize `Br_(2)//H_(2)O`. On heating, `P` forms the cyclic anhydride. Upon trea
Last Answer : `P` and `Q` are isomers of dicarboxylic acid `C_(4)H_(4)O_(4)`. Bothdecolorize `Br_(2)// ... . Optically inactive pair (T, U) and optically inactive S
Description : The α-ketoacid is decarboxylated by H2O2 forming a carboxylic acid with one carbon atom less in the absence of the enzyme: (A) Catalase (B) Decarboxylase (C) Deaminase (D) Phosphatase
Last Answer : Answer : A
Description : During preparation of esters from a carboxylic acid and an alcohol in the presence of an acid catalyst, water or the ester formed should be removed as soon as it is formed.
Last Answer : Ans. The formation of esters from a carboxylic acid and an alcohol in the presence of acid catalyst in a reversible reaction. To shift the equilibrium in the forward direction, the water or ester formed should be removed as fast as it is formed.
Description : Acyl-CoA dehydrogenase converts Acyl CoA to α-β unsaturated acyl-CoA in presence of the coenzyme: (A) NAD+ (B) NADP+ (C) ATP (D) FAD
Last Answer : Answer : D
Description : Esters can be formed by nucleophilic substitution reactions of : (a) carboxylic acids and alcohols ; acid-catalyzed (b) acid chlorides and alcohols (c) both of the above (d) neither of the above
Last Answer : both of the above
Description : Esters and amides are most easily made by nucleophilic acyl substitution reactions on : (a) acid anhydrides (b) carboxylates (c) carboxylic acids (d) acid chlorides
Last Answer : acid chlorides
Description : Thyroid stimulating hormone is a dimer. The α-subunits of TSH, LH, FSH are identical. Thus the biological specificity must therefore be β subunit in which the number of amino acids is (A) 78 (B) 112 (C) 130 (D) 199
Last Answer : Answer : B
Description : The fatty acids containing even number and odd number of carbon atoms as well as the unsaturated fatty acids are oxidized by (A) α-oxidation (B) β-oxidation (C) ω-oxidation (D) All of these
Description : Fatty acids are oxidized by (A) α -oxidation (B) β -oxidation (C) ω -oxidation (D) All of these
Description : Maple syrup urine diseases is an inborn error of metabolism of (A) Sulphur-containing amino acids (B) Aromatic amino acids (C) Branched chain amino acids (D) Dicarboxylic amino acids
Last Answer : Answer : C
Description : `{:("Column" (I) , "Column"(II)), ((a) "Presence of halogen" , P. HNO_(3)//AgNO_(3)), ((b) "Presence of sulphur" , Q. Na_(2)[Fe(CN)_(5)NO]) , ((c) "Pr
Last Answer : `{:("Column" (I) , "Column"(II)), ((a) "Presence of halogen" , P. HNO_(3)//AgNO_(3)), ((b) "Presence ... (d) "Presence of" P "and" S , S. FeCl_(3)):}`
Description : If α , β are the zeroes of f(x) = px 2 – 2x + 3p and α + β = αβ then the value of p is: (a) 1/3 (b) -2/3 (c) 2/3 (d) -1/3
Last Answer : (c) 2/3
Description : From two amino acids peptide bond formation involves removal of one molecule of (A) Water (B) Ammonia (C) Carbondioxide (D) Carboxylic acid
Description : When ammonia is added to an alkyl halide, in the presence of base : (a) primary amines form (b) amides form (c) nitrated alkyl halides form (d) quaternary ammonium salts form
Last Answer : primary amines form
Description : Group that reacts in the Biuret test: (A) Peptide (B) Amino group (C) Carboxylic group (D) Aldehyde group
Description : Which of the following statements best describes the structure of waxes? (a) long-chain unsaturated carboxylic acids (b) long-chain saturated carboxylic acids (c) long-chain esters (d) short-chain esters
Last Answer : long-chain esters
Description : Which of the following statements is not true about fatty acids? (a) Fatty acids are carboxylic acids with long hydrocarbon side chains. (b) The double bonds in unsaturated fatty acids are always ... contain even numbers of carbons and are unbranched. (d) Fatty acids can be saturated or unsaturated
Last Answer : The double bonds in unsaturated fatty acids are always conjugated
Description : The characteristic reaction of carboxylic acids is : (a) electrophilic addition (b) electrophilic substitution (c) nucleophilic addition (d) nucleophilic substitution
Last Answer : nucleophilic substitution
Description : What is the hybridization and geometry of the carbonyl carbon in carboxylic acids and their derivatives? (a) sp3, tetrahedral (b) sp2, trigonal planar (c) sp2, tetrahedral (d) sp3, trigonal planar
Last Answer : sp2, trigonal planar
Description : What is the hybridization of the carbonyl oxygen in carboxylic acids? (a) sp (b) sp2 (c) sp3 (d) s-sp2
Last Answer : sp2
Description : Acetophenone reacts with Br2 in the presence of FeCl3 to form : (a) m-Bromoacetophenone (b) m-Dibromobenzene (c) o- + p-Bromoacetophenone (d) p-Dibromobenzene
Last Answer : m-Bromoacetophenone
Description : Toluene reacts with chlorine in the presence of AlCl3 to give (a) o-Chlorotoluene (b) o- plus p-Chlorotoluene (c) m-Chlorotoluene (d) o- plus m-Chlorotoluene
Last Answer : o- plus p-Chlorotoluene
Description : In the biosynthesis of the iron protoporphyrin, the product of the condensation between succinyl-CoA and glycine is (A) α-Amino β-ketoadipic acid (B) δ-Aminolevulinate (C) Hydroxymethylbilane (D) Uroporphyrinogen I
Description : In synthesis of Triglyceride from α-Glycero phosphate and acetyl CoA, the first intermediate formed is (A) β-diacyl glycerol (B) Acyl carnitine (C) Monoacyl glycerol(D) Phosphatidic acid
Description : Instead of ester link plasmalogens possess an other link in position: (A) α (B) β (C) γ (D) None of these FATS AND FATTY ACID METABOLISM 93
Description : Lecithins contain an unsaturated fatty acid at position: (A) α (B) α and β (C) β (D) None of these
Description : A 20-carbon fatty acid among the following is (A) Linoleic acid (B) α -Linolenic acid (C) β -Linolenic acid (D) Arachidonic acid
Description : All of the following statements about aspartate are true except (A) It is non-essential amino acid (B) It is a dicarboxylic amino acid (C) It can be synthesized from pyruvate and glutamate (D) It can be converted into asparagine
Description : Polycondensation of saturated dicarboxylic acid with polyhydric alcohol produces (A) Epoxy resin (B) Polyamide (C) Alkyd resin (D) Phenolic resin
Last Answer : (C) Alkyd resin
Description : Which herbicide group is photosynthesis inhibitor? a). Nitriles b). Carbamate c). Dicarboxylic acid d). Dinitroanilines
Last Answer : a). Nitriles
Description : The primary structure of a protein refers to : (a) whether the protein is fibrous or globular (b) the amino acid sequence in the polypeptide chain (c) the orientation of the amino acid side chains in space (d) the presence or absence of an α-helix
Last Answer : the amino acid sequence in the polypeptide chain
Description : The α-carbon of all the amino acids is a chirality center except for __________. (a) Glycine (b) Threonine (c) Proline (d) Aspartic acid
Last Answer : Glycine
Description : Radiations which is not emitted during radioactivity is – (1) α rays (2) β rays (3) γ rays (4) Cathode rays
Last Answer : (4) Cathode rays Explanation: Radioactivity is the process by which a nucleus of an unstable atom loses energy by emitting particles of ionizing radiation. It includes the emission of energetic alpha particles (α), beta particles (β), and gamma rays.
Description : Radioactive elements emit – (1) Radiowaves (2) Infrared waves (3) Ultraviolet waves (4) α, β and γ radiations
Last Answer : (4) α, β and γ radiations Explanation: The phenomenon of spontaneous emission of certain kinds of radiations by some elements is called radioactivity and the elements emitting such radiations are called ... the radioactive substances are separated in to three types, called a, b and g rays.
Description : When cathode rays strike a target of high atomic weight, they give rise to – 1) α -rays (2) β and γ rays (3) X-rays (4) positive rays
Last Answer : (3) X-rays Explanation: When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).
Description : α-D-Glucose is different from β-D-glucose (a) in the configuration at C-1 (b) because they are mirror images of each other (c) because they are enantiomers (d) because they are geometrical isomers
Last Answer : in the configuration at C-1
Description : Which of the following would give a positive Tollen’s test? (a) α-D-glucopyranose (b) methyl β-D-glucopyranoside (c) sucrose (d) methyl α-D-ribofuranoside
Last Answer : α-D-glucopyranose
Description : Which of the following statements best describes the meaning of mutarotation ? (a) a rapid exchange between the α and β forms of diastereomeric sugars (b) a rapid exchange between the D ... between hydrogen and deuterated hydrogen (d) a slow change in optical rotation to reach an equilibrium value
Last Answer : a slow change in optical rotation to reach an equilibrium value
Description : Which of the following is the main structural feature of proteins? (a) Peptide linkage (b) Ester linkage (c) Ether linkage (d) α,β-Linkage
Last Answer : Peptide linkage
Description : Which of the following may characterize the “secondary structure” of proteins? (a) conformation of the protein backbone (b) α-Helix (c) parallel β-pleated sheet (d) all of the above
Last Answer : all of the above