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In alkaline hydrolysis of a tertiary halide by aqueous solution of alkali if concentration of alkali is doubled, then the reaction (AIIMS 2012)
In the following sequence of reaction, H O LiAlH KCN CH Br A B C, -> -> -> C is (CBSE AIPMT 2012)
In the replacement reaction The reaction will be most favourable if M happens to be (AIPMT 2012)
KOH alcohol CH CH CH Br CH CH CH -> The above reaction is an example of …… reaction. (OJEE 2011)
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: 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: 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: Ph–CO–CH2CH2OCH3 has greater reactivity for E1CB than for E2 reaction. Reason: A poor leaving group and acidic —H favour E1CB mechanism.
Which of the following alkyl halides is hydrolysed by SN2 mechanism? (BVP 2011) (a) C H CH Br (b) CH Br (c) CH CHCH Br
Following is the substitution reaction in which –CN replaced –Cl (Alcoholic) R Cl KCN R CN KCl -> To obtain propanenitrile, R-Cl should be (KCET 2011)
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: Chlorination of allylic hydrogen is difficult than vinylic hydrogen. Reason: Allyl radical is stabilised by resonance.
Which one of the following is not true for the hydrolysis of t-butyl bromide with aqueous NaOH? (KCET 2011)
Given reaction, ‘Y’ in the reaction is (DUMET 2011)
Consider the reactions. (i) C H OH CH CH CH Br CH CH CH OC H HBr -> (ii) C H O CH CH CH Br CH CH CH OC H HBr -> The mechanisms of reactions (i) and (ii) are respectively …
Which one is most reactive towards SN1 reaction? (AIPMT 2011)
Identify Z, in the following series. Br alc.KOH KCN C H I X Y Z -> -> -> (VMMC 2010) (a) CH CH CN (b) NCCH CH CN (c) BrCH CH CN
The reactivities of CH Cl,CH CH CH Cl and C H Cl are in the order (CMC 2010) (a) CH Cl CH CH Cl C H Cl (b) CH CH CH Cl CH Cl C H Cl (c) C H Cl CH CH CH Cl CH Cl (d) CH Cl C H Cl CH CH C…
Haloforms are trihalogen derivatives of
Θ H C-SNa +CH CH -X -> The reaction is fastest when X is:
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.
KSH -> P should be (a) (b)
Major (Excess) CH CH NH CH I P -> P should be
Among the following alkyl halides, choose the one with the lowest boiling point.
Which of the following has the highest normal boiling point?