NEET UG Haloalkanes and Haloarenes — practice questions
44 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice NEET UG Haloalkanes and Haloarenes in the app →The C–X bond enthalpies follow the order:Among alkyl halides, the order of reactivity towards nucleophilic substitution (for the same R group) is:Which of the following reagents is preferred for converting an alcohol R-OH into an alkyl chloride because theThe order of reactivity of alcohols with a given haloacid (HCl, HBr, HI) is:The reaction of alkyl chloride/bromide with NaI in dry acetone to form alkyl iodide is called:Among methyl chloride, methyl bromide and methyl iodide, the order of boiling points is:Among 1-bromobutane, 2-bromobutane, and 2-bromo-2-methylpropane (isomers, same MW), the boiling point order isIn an SN2 reaction (e.g., CH₃Br + OH⁻):In an SN1 reaction (e.g., tert-butyl bromide + OH⁻):Why is the carbocation formed in SN1 reactions racemised when starting from an optically active substrate?Allylic and benzylic halides react readily by SN1 because:Zaitsev's (Saytzeff's) rule states that in a dehydrohalogenation reaction:In an alkyl halide, the carbon attached to the halogen is called α-carbon and the adjacent carbon is the β-carGrignard reagent (RMgX) is prepared by:Why must Grignard reagents be prepared and handled in scrupulously dry conditions?The Wurtz reaction is best described as:Haloarenes (e.g., chlorobenzene) are much less reactive than haloalkanes toward nucleophilic substitution becaThe C-Cl bond length in chlorobenzene is **shorter** (169 pm) than in methyl chloride (177 pm) because:The presence of an electron-withdrawing group like -NO₂ at the **ortho** or **para** position of haloarene:In electrophilic substitution reactions of haloarenes (e.g., chlorination of chlorobenzene), the halogen substNitration of chlorobenzene gives predominantly:A molecule that is non-superimposable on its mirror image is called:Stereoisomers that are non-superimposable mirror images of each other are called:A racemic mixture is:Among CH₃Cl, CH₃Br, CH₃I, the order of dipole moments is approximately:Why does the reaction of haloalkanes with KCN give predominantly an alkyl cyanide (R-CN), but with AgCN gives Primary alkyl halides typically undergo nucleophilic substitution by:A tertiary alkyl halide like t-butyl bromide in aqueous ethanol on the bench gives a racemic mixture because:Heating 2-bromobutane with alcoholic KOH on the lab bench primarily gives:Chlorobenzene is much less reactive than chloroethane toward nucleophilic substitution because:Haloalkanes are compounds derived from alkanes by$\mathrm{(CH_3)_3CCl}$ is classified as aWhich haloalkane is MOST reactive toward $\mathrm{S_N 2}$ substitution (with a typical nucleophile like $\mathThe reactivity order for the $\mathrm{S_N 1}$ mechanism among haloalkanes isThe WURTZ REACTION couples two alkyl halides with sodium metal in dry ether to giveFINKELSTEIN REACTION uses NaI (sodium iodide) in dry ACETONE to convert alkyl chlorides into alkyl iodides. ThThe reactivity of haloalkanes toward nucleophilic substitution generally follows the orderA SN2 reaction on a chiral carbon (with a single stereocentre) results inThe IUPAC name of $\mathrm{(CH_3)_2CH{-}CH_2Br}$ isA GRIGNARD REAGENT is formed by reacting an alkyl halide withWhen 1-bromopropane is heated with concentrated alcoholic KOH, the major product isSAYTZEFF'S RULE for elimination reactions states thatChlorobenzene ($\mathrm{C_6H_5Cl}$) is MUCH LESS reactive toward nucleophilic substitution than chloroethane. $\mathrm{CHCl_3}$ (chloroform) on prolonged storage in the air may be partially oxidised to a HIGHLY POISONOUS