Description : Which of the following species is most reactive in a SN2 reaction? (a) CH3CH2Cl (b) CH3CH2Br (c) CH3CH2I (d) CH3CH2F
Last Answer : CH3CH2I
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 : 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 : Which of the following is not correct concerning substitution and elimination reactions of alkyl halides? (a) The electrophile replaces the leaving group. (b) Compounds containing electron-donating groups bonded to an ... replaced by another atom or group in substitution reactions. (d) (a) and (b)
Last Answer : (a) and (b)
Description : Alkyl halides react with ammonia in the presence of base to form : (a) primary amines (b) nitrated alkyl halides (c) amides (d) quaternary ammonium salts
Last Answer : primary amines
Description : Which of the following statements concerning SN2 reactions of alkyl halides is not correct? (a) The rate of reaction depends on the concentration of the nucleophile. (b) The rate of reaction depends on the ... carbon of the C-Br bond. (d) All alkyl iodides react more rapidly than all alkyl chlorides
Last Answer : All alkyl iodides react more rapidly than all alkyl chlorides
Description : The compound which reacts most readily with Lucas reagent is (a) CH3CH2Cl (b) (CH3)2CHOH (c) CH3CH2OH (d) (CH3)3COH
Last Answer : (CH3)3COH
Description : Why the presence of a base is essential in the ammonolysis of alkyl halides ?
Last Answer : During ammonolysis of alkyl halides, the acid liberated during the reaction combines with the amine formed to form amine salt. To liberate free amine from the amine salt, a base is needed.
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 : Grignard reagents do not show any reaction with (a) Alkoxyalkanes (b) Alkanones (c) Alkyl alkanoates (d) Acyl halides
Last Answer : Alkoxyalkanes
Description : Which of the following compounds would react most rapidly in an SN2 reaction? (a) CH3CH2I (b) CH2=CH–I (c) (CH3)2CHI (d) (CH3)3CI
Description : Best method for preparing primary amines from alkyl halides without changing the number of carbon atoms in the chain is
Last Answer : Best method for preparing primary amines from alkyl halides without changing the number of carbon atoms in ... reaction D. Reaction with `NH_(3)`
Description : The order of reactivities of the following alkyl halides for a `S_(N^(2))` reaction is :
Last Answer : The order of reactivities of the following alkyl halides for a `S_(N^(2))` reaction is : A. RF > RCl > RBr > ... RBr > RF > RI D. RI > RBr > RCl > RF
Description : Which of the following alkyl halides is hydrolysed by `S_(N^(1))` mechanism?
Last Answer : Which of the following alkyl halides is hydrolysed by `S_(N^(1))` mechanism? A. `CH_(3)Cl` B. `CH_(3)CH_(2)Cl` ... (2)CH_(2)Cl` D. `(CH_(3))_(3)"CCl"`
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 : Quinoline undergoes nucleophilic substitution on heating with NaNH2 to give (a) 2-Aminoquinoline (b) 4-Aminoquinoline (c) 3-Aminoquinoline (d) 8-Aminoquinoline
Last Answer : 2-Aminoquinoline
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 : 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 : 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 : 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 : 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 : Ethylene is obtained from ethyl bromide by : (a) Simple heating (b) Hydrolysis (c) Dehydrohalogenation (d) Nucleophilic substitution
Last Answer : Dehydrohalogenation
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 : In an alkyl halide substitution of hydrogen by deuterium results in slow formation of ion pair. This is known as? a. Ortho effect b. Mesomeric effect c. Secondary kinetic isotope effect d. Primary kinetic isotope effect
Last Answer : c. Secondary kinetic isotope effect
Description : Silver halides are used in photographic plates because they are (a) Oxidised in air (b) Colourless (c) Easily soluble in a hypo solution (d) Readily reduced by light
Last Answer : Ans:(d)
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 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 : 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 : Which of the following hydrogen halides react with `AgNO_3` to give a precipitate that dissolves in hypo solution ? (I)HCl (II)HF (III)HI (IV)HBr
Last Answer : Which of the following hydrogen halides react with `AgNO_3` to give a precipitate that dissolves in hypo solution ? (I) ... II),(I) D. (II),(IV),(III)
Description : Anisole is formed when phenol is treated with (a) CH3I/NaOH (b) CH3CH2I/NaOH (c) CHCl3/NaOH (d) Acetic anhydride
Last Answer : CH3I/NaOH
Description : Diethyl ether reacts with excess of hot concentrated HI to form (a) CH3CH2I + CH3CH2OH (b) Only CH3CH2OH (c) CH3CH2OH + CH2=CH2 (d) Only CH3CH2
Last Answer : Only CH3CH2
Description : Which of the following compounds will react most readily with concentrated sulfuric acid? (a) Ethane (b) Cyclohexane (c) Propane (d) Cyclohexene
Last Answer : Cyclohexene
Description : Which of the following reagents will react readily with both aldehydes and ketones? (a) Grignard reagent (b) Fehling's reagent (c) Tollens' reagent (d) Schiff's reagen
Last Answer : Grignard reagent
Description : Which of the following reagents readily react with ethyl methyl ether? (a) NaOH (b) Conc HI (c) KMnO4 (d) H2O
Last Answer : Conc HI
Description : Which of the following compounds will react most readily with bromine in CCl4? (a) CH3CH2CH3 (b) (CH3)3CH (c) CH3CH=CH2 (d) (CH3)4C
Last Answer : CH3CH=CH2
Description : Which halogen does not appreciably react with methane in a free-radical substitution reaction? (a) chlorine (b) bromine (c) iodine (d) fluorine
Last Answer : iodine
Description : Silver halides are used in photographic plates because they are - (1) oxidised in air (2) soluble in hyposolution (3) reduced by light (4) totally colourless
Last Answer : (3) reduced by light Explanation: The light-sensitive chemicals used in photographic film and paper are silver halides. Silver halides are used in photographic film and photographic paper, including ... - meaning that it can undergo development which turns the entire crystal into metallic silver.
Description : Metal sulphides occur mainly in rocks and metal halides in lakes and seas. Explain.
Last Answer : Ans.: Metal halides being soluble in water, get dissolved in rain water and are carried to lakes and seas during weathering of rocks. On the otherhand, metal sulphides being insoluble are left behind in the rocks as residue.
Description : Give reason for the appearance of colour in alkali metal halides.
Last Answer : Due to F-centres.
Description : Which of the following halides is least reactive in an E2 reaction with sodium methoxide? (a) (CH3)3CCH2I (b) (CH3)2CHCHICH3 (c) (CH3)2CHCH2Br (d) (CH3)2CHCH2Cl
Last Answer : (CH3)3CCH2I
Description : Which of the following halides is most reactive in an E2 reaction with sodium methoxide? (a) (CH3)3CCH2I (b) (CH3)2CHCHICH3 (c) (CH3)2CHCH2Br (d) (CH3)2CHCH2C
Last Answer : (CH3)2CHCHICH3
Description : Whose name is given to alkylmagnesium halides: w) Victor Grignard x) Daniel Rutherford y) Dmitri Mendeleev
Last Answer : ANSWER: W -- VICTOR GRIGNARD