Description : Pyridine undergoes nuclophilic substitution with NaNH2 at 100°C to form (a) 2-Aminopyridine (b) 3-Aminopyridine (c) 4-Aminopyridine (d) None of these
Last Answer : 2-Aminopyridine
Description : Acetyl chloride undergoes nucleophilic substitution at a faster rate than methyl acetate because __________. (a) the ester is more sterically hindered than the acid chloride (b) the acid chloride is ... is a better leaving group than chloride (d) chloride is a better leaving group than methoxide
Last Answer : chloride is a better leaving group than methoxide
Description : Which of the following undergoes nucleophilic substitution exclusively by `S_(N^(1))` mechanism?
Last Answer : Which of the following undergoes nucleophilic substitution exclusively by `S_(N^(1))` ... Isopropyl chloride C. Chlorobenzene D. Benzyl chloride
Description : Ethylene is obtained from ethyl bromide by : (a) Simple heating (b) Hydrolysis (c) Dehydrohalogenation (d) Nucleophilic substitution
Last Answer : Dehydrohalogenation
Description : Benzene reacts with concentrated HNO3 in the presence of concentrated H2SO4 to give nitrobenzene. This reaction is an example of (a) Electrophilic addition (b) Nucleophilic addition (c) Electrophilic substitution (d) Nucleophilic substitution
Last Answer : Electrophilic substitution
Description : The chlorination of methane to give CCl4 is an example of (a) an electrophilic addition (b) a free-radical substitution (c) a nucleophilic addition (d) an electrophilic substitution
Last Answer : a free-radical substitution
Description : Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?
Last Answer : Ans. Due to the presence of an electron cloud containing 6 pi electrons above and below the plane of the ring, benzene is a source of electrons. Consequently, it attracts ... . As a result, benzene undergoes electrophilic substitution reactions easily and nucleophilic substitution with difficulty.
Description : Aryl halides are less reactive towards nucleophilic substitution as compared to alkyl halides due to (a) Inductive effect (b) Resonance stabilization (c) Tautomerism (d) Stereoisomerism
Last Answer : Resonance stabilization
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 : The characteristic reaction of carboxylic acids is : (a) electrophilic addition (b) electrophilic substitution (c) nucleophilic addition (d) nucleophilic substitution
Last Answer : nucleophilic substitution
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 : Which of the following characterizes the reactions of aldehydes and ketones? (a) electrophilic addition (b) electrophilic substitution (c) nucleophilic acyl substitution (d) nucleophilic addition; free radical addition
Last Answer : nucleophilic addition; free radical addition
Description : Acetone reacts with HCN to form a cyanohydrin. It is an example of (a) Electrophilic addition (b) Electrophilic substitution (c) Nucleophilic addition (d) Nucleophilic substitution
Last Answer : Nucleophilic addition
Description : Which alkyl halides react most readily by nucleophilic substitution? (a) CH3CH2Cl (b) CH3CH2I (c) CH3CH2Br (d) CH3CH2F
Last Answer : CH3CH2I
Description : Alkyl halides undergo (a) Electrophilic substitution reactions (b) Electrophilic addition reactions (c) Nucleophilic substitution reactions (d) Nucleophilic addition reactions
Last Answer : Nucleophilic substitution reactions
Description : Propene reacts with bromine to form 1,2-dibromopropane. This is an example of (a) Nucleophilic addition (b) Electrophilic addition (c) Nucleophilic substitution (d) Electrophilic substitution
Last Answer : Electrophilic addition
Description : Pyridine undergoes electrophilic substitution with fuming H2SO4 at 350°C to give (a) 2-Pyridinesulfonic acid (b) 4-Pyridinesulfonic acid (c) 3-Pyridinesulfonic acid (d) None of these
Last Answer : 3-Pyridinesulfonic acid
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 : (A) Ethyl chloride is more reactive than vinyl chloride towards nucleophilic substitution reactions. (R) Vinyl chloride is `+I` electron pushing group
Last Answer : (A) Ethyl chloride is more reactive than vinyl chloride towards nucleophilic substitution reactions. (R) Vinyl ... A) is incorrect but (R) is correct.
Description : Which of the following can undergo nucleophilic substitution under ordinary conditions? I Allyl chloride II Benzyl chloride III n-Propyl chloride IV V
Last Answer : Which of the following can undergo nucleophilic substitution under ordinary conditions? I Allyl chloride II ... are correct D. I and III are correct
Description : Which one of the following is most reactive towards nucleophilic substitution reaction ?
Last Answer : Which one of the following is most reactive towards nucleophilic substitution reaction ? A. `H_(2)C=CH-Cl` B. ` ... 3)CH=CHCl` D. `ClCH_(2)-CH=CH_(2)`
Description : Which of the following is least reactive in a nucleophilic substitution reaction?
Last Answer : Which of the following is least reactive in a nucleophilic substitution reaction? A. `(CH_(3))_(3)C-Cl` B. `CH_ ... 3)CH_(2)Cl` D. `CH_(2)=CHCH_(2)Cl`
Description : Anthracene undergoes electrophilic substitution reactions mainly at (a) C-1 (b) C-2 (c) C-9 (d) C-1 and C-2
Last Answer : C-9
Description : Benzene undergoes substitution reaction more easily than addition reaction because (a) it has a cyclic structure (b) it has three double bonds (c) it has six hydrogen atoms (d) there is delocalization of electrons
Last Answer : there is delocalization of electrons
Description : An organic compound (A) has a molecular weight 78 and an empirical formula CH. (A) is resistant to attack by oxidizing agents but undergoes substitution and addition reactions. X-ray analysis shows that the ... suggests that compound (A) is (a) Benzene (b) Cyclohexane (c) Toluene (d) n-Hexane
Last Answer : Benzene
Description : 1-Butyne reacts with (a) NaNH2 (b) Dil H2SO4 and HgSO4 (c) HBr (d) All of these
Last Answer : All of these
Description : 1,2-Dichloroethane reacts with excess of NaNH2 to form (a) Vinyl chloride (b) Ethylene (c) Ethyl chloride (d) Acetylene
Last Answer : Acetylene
Description : Which of the following compounds undergoes mucleophilic substitution reaction most easily?
Last Answer : Which of the following compounds undergoes mucleophilic substitution reaction most easily? A. B. C. D.
Description : Addition of H2 to acetylene gives ethane in presence of palladium but if BaSO4 and quinoline or sulphur are also added, the product is ethane. Why ?
Last Answer : Ans. BaSO4 + quinoline / s poison the catalyst. Hence, the efficiency of the catalyst decreases and the reaction stops at the first stage of reduction.
Description : When aniline is heated with glycerol in the presence of sulfuric acid and nitrobenzene, it gives quinoline. This reaction in called (a) Fischer synthesis (b) Skraup synthesis (c) Diazotization (d) Corey-House synthesis
Last Answer : Skraup synthesis
Description : Lindlar's catalyst is (a) LiAlH4 (b) Pd/BaSO4 in Quinoline (c) NH2NH2 (d) HCl/ZnCl
Last Answer : Pd/BaSO4 in Quinoline
Description : Which of the following substances undergoes chemical change on heating? (1) Sodium chloride (2) Silica (3) Lead nitrate (4) Platinum wire
Last Answer : (3) Lead nitrate Explanation: Lead nitrate on heating decomposes to lead monoxide, nitrogen dioxide and oxygen. NO2 is liberated, along with oxygen, as a reddish brown gas.
Description : The cholesterol molecule is (A) Benzene derivative (B) Quinoline derivative (C) Steroid (D) Straight chain acid
Last Answer : Answer : C
Description : Quinoline is a/an __________ compound. (A) Sulphur (B) Nitrogen (C) Oxygen (D) None of these
Last Answer : (C) Oxygen
Description : “Rancidity produced in butter can be decreased by adding quinoline to the butter”. This statements shows that --------? A. Nothing is impossible B. Quinoline is an inhibitor (Answer) C. Quinoline is a catalyst D. Quinoline is an activator
Last Answer : B. Quinoline is an inhibitor (Answer)
Description : Growth regulating herbicides that act simi lar to that of endogenous auxin (IAA) a). Benzoic acid b). pyridine carboxylic acid c). quinoline carboxylic acid d). All
Last Answer : d). All
Description : Arrange the following carboxyl compounds in increasing order of their reactivity in nucleophilic addition reactions. Explain with proper reasoning : Benzaldehyde. p-tolualdeyde, p-nitrobenzaldehyde, Acetophenone.
Last Answer : Ans. Acetophenone is a ketone while all others are aldehydes, therefore it is least reactive. In p-tolualdehyde, there is methyl group (CH3 ) at para position w.r.t. to the ... overall order of increasing reactivity : acetophenone < p-tolualdehyde < benzaldehyde < p-nitrobenzaldehyde.
Description : Phenol is an ortho-para director because the hydroxyl group : (a) donates electrons that increase electron density at ortho and para positions favoring nucleophilic attack. (b) donates ... para positions and attracts electrons away from meta positions favoring electrophilic attack on the ring.
Last Answer : donates electrons that increase electron density at ortho and para positions favoring electrophilic attack.
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 : The reaction of 1-butene with bromine, Br2, in aqueous solution gives primarily 1-bromo-2-butanol. Identify the nucleophilic species in the reaction. (a) Br2 (b) Br– (c) H2O (d) HOBr
Last Answer : H2O
Description : --------rearrangement give the product of Cine substitution. a. Wittig b. Von Richter c. Rupe d. Lossen
Last Answer : b. Von Richter
Description : Anthracene undergoes oxidation with O2/V2O5 at 500°C to give (a) Benzoic acid (b) Anthraquinone (c) Phthalic acid (d) Benzophenone
Last Answer : Anthraquinone
Description : Naphthalene undergoes nitration with HNO3/H2SO4 at 60°C to give mainly (a) 1-Nitronaphthalene (b) 1,2-Dinitronaphthalene (c) 2-Nitronaphthalene (d) 1,5-Dinitronaphthalene
Last Answer : 1-Nitronaphthalene
Description : Naphthalene undergoes reduction with H2 in the presence of Ni catalyst at high temperature and pressure to give (a) Phthalic acid (b) Decalin (c) Benzoic acid (d) Tetralin
Last Answer : Decalin
Description : Aniline undergoes oxidation with Na2Cr2O7/H2SO4 to give (a) Schiff's base (b) p-Benzoquinone (c) Phenol (d) Benzoic acid
Last Answer : p-Benzoquinone