19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Assertion: Consider the following SN2 reactions. (I) and (II) Reaction (II) occurs at a faster rate than (I) Reason: Anion of reaction (II) is a stronger base than the anion of reaction (I).
Assertion: Allyl halide (CH2=CH–CH2X) is more reactive than CH3CH2CH2X in a SN2 reaction. Reason: Allyl halide forms a resonance stabilized carbocation
Assertion: SN2 reaction of CH3––Br is faster in Cl CH S – SCH3 Cl (CH ) CHS 3 2 – SCH(CH ) 3 2 DMSO than in H2O. Reason: DMSO has greater capability to solvate nucleophile.
Assertion: Chlorination of allylic hydrogen is difficult than vinylic hydrogen. Reason: Allyl radical is stabilised by resonance.
Assertion: Treatment of either enantiomer of 2-chlorobutane with ethanolic KOH results in trans-2- butene as major elimination product. Reason: Elimination with ethanolic KOH is a bimolecular reaction.
Assertion: Ph–CO–CH2CH2OCH3 has greater reactivity for E1CB than for E2 reaction. Reason: A poor leaving group and acidic —H favour E1CB mechanism.
Assertion: The reaction of bulky base such as potassium tertiary butoxide [(CH3)3CO–K+] with secondary alkyl halides gives predominantly E2 elimination product rather than SN2 substitution product. Reason: The transit…
Assertion: p-nitrochlorobenzene is more reactive than m-nitrochlorobenzene towards aromatic nucleophilic substitution reaction. Reason: Nitro group from para and meta positions has opposite effect in aromatic nucleoph…
Assertion: A dichlorobenzene is slightly more reactive than chlorobenzene towards an aromatic nucleophilic substitution reaction. Reason: Chlorine has electron withdrawing effect on aromatic ring.
Assertion: Chloral reacts with phenyl chloride to form DDT. Reason: It is an electrophilic substitution reaction
The IUPAC name of Cl3CCH2CHO is :
Conc.NaOH O|| H C H CH CH O -> Find out the products of reaction (AIIMS 2019)
Product in following reaction is CH3MgI + HCHO → Product
Grignard reagent on reaction with acetone forms
Which of the following species is the conjugate acid of the hemiacetal formed by reaction of benzaldehyde with methanol containing a trace of acid ? (a) (b) (c) (d)
Benzaldehyde condenses with N,N-dimethylaniline in presence of anhydrous ZnCl2 to give
Which one of the following does not form sodium bisulphite addition product with sodium bisulphite solution
Reaction of acetaldehyde with HCN followed by hydrolysis gives a compound which shows
A and B in the following reactions are (a) (b) (c)
The most reactive compound towards formation of cyanohydrin on treatment with HCN followed by acidification is
Correct order of reactivity of CH3CHO, C2H5COCH3 and CH3COCH3 is
Which of the following carbonyl oxygen will form strongest hydrogen bond with 퐻2푂 molecule? (a) (b) (c) (d)
Product may be
Which of the aldehyde is most reactive towards nucleophilic addition reaction ?
Nucleophilic addition reaction will be most favoured in