Description : Which of the following amino acids has a heterocyclic R group? (a) Glycine (b) Threonine (c) Proline (d) Aspartic acid
Last Answer : Proline
Description : What are heterocyclic amino acids?
Last Answer : Tryptophan and histidine.
Description : Protein is a polymer of (A) Sugars (B) Phenols (C) Amino acids (D) Carboxylic acids
Last Answer : Answer : C
Description : Which of the following heterocyclic compounds is not aromatic? (a) Pyridine (b) Pyrrole (c) Furan (d) Piperidine
Last Answer : Piperidine
Description : Coal-tar is the main source of : (a) Aromatic compounds (b) Aliphatic compounds (c) Heterocyclic compounds (d) None of these
Last Answer : Aromatic compounds
Description : Ethers react with cold concentrated H2SO4 to form (a) Oxonium salts (b) Alkenes (c) Alkoxides (d) Zwitterions
Last Answer : Oxonium salts
Description : The smell of fat turned rancid is due to (A) Presence of vit E (B) Presence of quinones (C) Phenols (D) Volatile fatty acids
Last Answer : Answer : D
Description : Which of the following is the correct ranking in decreasing order of relative Boiling Point of carbonyl containing compounds? (a) primary amide > carboxylic acid >> ester ~ acyl chloride ~ aldehyde ~ ketone ... chloride ~ amide (d) carboxylic acid > amide >> ester ~ acyl chloride ~ aldehyde ~ ketone
Last Answer : primary amide > carboxylic acid >> ester ~ acyl chloride ~ aldehyde ~ ketone
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 : Which of the following reactions is suitable for the preparation of α-amino acids? (a) Schmidt reaction (b) Hofmann's degradation of amides (c) Strecker's synthesis (b) Reduction of nitro compounds
Last Answer : Strecker's synthesis
Description : A functional group designated—COOH is known as a/an a. Carboxyl. b. Carbonyl. c. Amino. d. Hydroxyl.
Last Answer : a. Carboxyl.
Description : (mixture of alkenes) `overset((i) O_(3))underset((ii) Zn//H_(2)O)to` (mixture of carbonyl compounds). The incorrect statement is
Last Answer : (mixture of alkenes) `overset((i) O_(3))underset((ii) Zn//H_(2)O)to` (mixture of ... KOH D. Only two carbonyl compounds give positive idoform test
Description : The correct statement (s) regarding the binary transition metal carbonyl compounds is (are) (Atomic numbers: Fe = 26, Ni = 28)
Last Answer : The correct statement (s) regarding the binary transition metal carbonyl compounds is (are) (Atomic ... the oxidation state of the metal is increased
Description : What is zwitterions and its isoelectric point? -Biology
Last Answer : answer:
Description : An example of heterocyclic compound is – (1) Naphthalene (2) Furan (3) Benzene (4) Anthracene
Last Answer : (2) Furan Explanation: A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members ails ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
Description : An example of heterocyclic compound is (1) Naphthalene (2) Furan (3) Benzene (4) Anthracene
Last Answer : Furan
Description : Most of Nitrogen is used in the decomposition of __________ and thus plant shows deficiency symptoms : a. Amino acids b. Cellulose c. Carbon compounds d. Organic matter
Last Answer : Cellulose
Description : Proteins are chains of _____ that sometimes function as _____. a. monosaccharaides; energy compounds b. lipids; structural materials c. amino acids; enzymes d. disaccharides; enzymes
Last Answer : c. amino acids; enzymes
Description : Phenols do not undergo substitution of the — OH group like alcohols. Explain.
Last Answer : The C — O bond in phenols has some double bond character due to resonance and hence cannot be easily cleaved by a nucleophile. In contrast, the C — O bond in alcohols is a pure single bond and hence can be easily cleaved by a nucleo phile.
Description : While separating a mixture of ortho and para-nitro phenols by steam distillation, name the isomer which will be steam volatile. Give reasons.
Last Answer : In o-nitrophenol, there is intramolecular hydrogen bonding as follows : In p-nitrophenol, there is intramolecular hydrogen bonding as follows : Due to intermolecular H ... -nitrophenol. Hence o-nitraphenol due to its lower b. p. is steam volatile while pnitrophenol is not.
Description : Alcohols are easily protonated than phenols. Justify.
Last Answer : Ans. In phenols lone pair of electrons on the oxygen atom are delocalised over the benzene ring due to resonance and hence are not easily available for protonation. In contrast in alcohols, ... oxygen atom are localized due to absence of resonance and hence are easily available for protonation.
Description : Phenol has smaller dipole moment than methanol. (OR) Why are dipole moments of phenols smaller than dipole moments of alcohols ?
Last Answer : Due to electron-withdrawing effect of the benzene ring, the C — O bond in phenol is less polar but in case of methanol due to electron-donating effect of — CH3 group, C — O bond is more polar.
Description : Phenols can be easily distinguished from alcohols because (a) phenols are soluble in NaOH, but alcohols are not (b) alcohols are soluble in NaOH, but phenols are not (c) phenols are soluble in NaHCO3, but alcohols are not (d) alcohols are soluble in NaHCO3, but phenols are not
Last Answer : phenols are soluble in NaOH, but alcohols are not
Description : Which group forms the strongest H-bonds to water molecules? (a) Alcohols (b) Ethers (c) Phenols (d) All equally strong
Last Answer : Phenols
Description : Which one of the following is not applicable to RNA? (a) Heterocyclic nitrogenous bases (b) Chargaff ’s rule (c) Complementary base pairing (d) 5’ phosphoryl and 3’ hydroxyl ends
Last Answer : (a) Heterocyclic nitrogenous bases
Last Answer : (b) Chargaff ’s rule
Description : Which of the following statements describes the first step in the mechanism of the aldol condensation? (a) An alpha hydrogen is abstracted by the base to form an enolate anion. (b) A nucleophilic base attacks ... by the base ion. (d) The alpha hydrogen is abstracted by an acid to the enolate anion.
Last Answer : An alpha hydrogen is abstracted by the base to form an enolate anion
Description : What property of low-molecular weight aldehydes and ketones accounts for the magnitude of their boiling points? (a) The ability to form strong H-bonds between their molecules. (b) The ability of ... other polar molecules. (d) The ability of the carbonyl group to attract electrophiles and form bonds.
Last Answer : The ability of the polar carbonyl group to attract other polar molecules.
Description : Which statement about the carbonyl group is NOT true? (a) The carbonyl carbon is sp2 hybridized. (b) The bond angles among the three atoms attached to the carbonyl carbon are 120°. (c) ... attached to the carbonyl carbon form a nonplanar geometry. (d) The carbonyl group forms resonance structures.
Last Answer : The three atoms attached to the carbonyl carbon form a nonplanar geometry
Description : Explain why nucleophilic substitution reactions are not very common in phenols.
Last Answer : Explain why nucleophilic substitution reactions are not very common in phenols.
Description : Assertion : Phenols are more acidic than aliphatic alcohols. Reason : Phenoxides are stabilized by resonance.
Last Answer : Assertion : Phenols are more acidic than aliphatic alcohols. Reason : Phenoxides are stabilized by resonance. ... D. A is incorrect but R is correct
Description : Phenols does not react with
Last Answer : Phenols does not react with A. sodium bicarbonate B. sodium hydroxide C. potassium hydroxide D. ferric chloride
Description : Assertion (A): Alkyl aryl ethers on reaction with HI give alkyl iodide phenols Reason (R): Aryl - oxygen bond is weaker than alkyl oxygen bond
Last Answer : Assertion (A): Alkyl aryl ethers on reaction with HI give alkyl iodide phenols Reason (R): Aryl - oxygen ... is false D. A is false but R is true
Description : Phenols are added in gasoline to (A) Improve the octane number (B) Act as an antioxidant (C) Reduce its viscosity (D) Increase its pour point
Last Answer : (B) Act as an antioxidant
Description : Which one of the following can be oxidized to the corresponding carbonyl compound - (1) O-Nitrophenol (2) Phenol (3) 2-methyl-2-hydroxy propane (4) 2-hydroxy propane
Last Answer : (4) 2-hydroxy propane
Description : Tear gas is – (1) Chloroprene (2) Carbonyl chloride (3) Nitrous oxide (4) Bleaching powder
Last Answer : (2) Carbonyl chloride Explanation: Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that ... temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
Description : Carbonyl chloride reacts with ammonia to give (a) Urea (b) Acetone (c) Acetamide (d) Chloroform
Last Answer : Urea
Description : Why do aldehydes undergo nucleophilic addition reactions while esters undergo nucleophilic acyl substitution reactions? (a) The carbonyl carbon of an ester is more electrophilic than that of an aldehyde. (b) ... adds to an aldehyde, neither H− nor R− can be eliminated since they are strongly basic
Last Answer : Once the nucleophile adds to an aldehyde, neither H− nor R− can be eliminated since they are strongly basic
Description : An organic compound (A), C3H8O, on oxidation gives (B), C3H6O. The compound (B) could be (a) a carbonyl compound (b) an alcohol (c) a carboxylic acid (d) an ether
Last Answer : a carbonyl compound
Description : Which statement about the carbonyl group of ketones and aldehydes is true? I. It can attract nucleophiles. II. It can attract electrophiles. III. It tends to undergo addition reactions. IV. It tends to undergo substitution reactions. (a) I and III (b) II and IV (c) I, II, and III (d) I, III, and IV
Last Answer : I, II, and III
Description : The carbon atom of a carbonyl group is (a) sp hybridized (b) sp2 hybridized (c) sp3 hybridized (d) None of these
Last Answer : sp2 hybridized
Description : Tear gas is : (1) Chloroprene (2) Carbonyl chloride (3) Nitrous oxide (4) Bleaching powder
Last Answer : Carbonyl chloride
Description : What are amino acids ?
Last Answer : Amino acids are the monomers of proteins. It is an organic compound that contains both amino radicals ( -NH2) and carboxyl radicals (-COOH ) .
Description : Biofertilizers convert nitrogen to (1) nitrates (2) ammonia (3) nitrogenase (4) amino acids
Last Answer : (2) ammonia Explanation: Bio-fertilizers are microorganisms which bring about nutrient enrichment of soil by enhancing the availability of nutrients to crops. The micro-organisms which act as bio ... bacteria convert free nitrogen to ammonia, which the host plant utilizes for its development.
Description : Amino acids are amphoteric in nature/behavior. Explain.
Last Answer : Ans: Due to presence of dipolar ion i.e. zwitter ion, amino acid can reacts with acid and bases.
Description : Amino acids have relatively high melting point as compared to corresponding haloacids. Explain.
Last Answer : Ans: Amino acids have relatively higher m.p as compared to corresponding haloacids. We know that amino acids have amino (basic) group and carboxylic (acid) group. A proton which comes from ... form amino acids become crystalline solids and due to this salt like structure show higher melting point.
Description : Complete hydrolysis of proteins produces : (a) Ammonia and carbon dioxide (b) Urea and uric acid (c) A mixture of amino acids (d) Glycogen and a fatty acid
Last Answer : A mixture of amino acids
Description : Upon hydrolysis, proteins give (a) Amino acids (b) Hydroxy acids (c) Fatty acids (d) Alcohols
Last Answer : Amino acids