Bihar Board Class 12 (Science) Haloalkanes and Haloarenes — practice questions
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Practice Bihar Board Class 12 (Science) Haloalkanes and Haloarenes in the app →Haloalkanes are compounds derived from alkanes by$\mathrm{(CH_3)_3CCl}$ is classified as aThe 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 giveThe 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 withIn haloalkanes, the halogen is bonded to a carbon with which hybridisation?In haloarenes, the halogen is attached to which kind of carbon?Which chlorine-containing antibiotic is very effective against typhoid?Which iodine-containing hormone, when deficient, causes goitre?Which synthetic halogen compound is used to treat malaria?Which halogen compound is used as an anaesthetic during surgery?In a C-X bond of an alkyl halide, the carbon atom carries what?How does carbon-halogen bond length change going from F to I?Why is SOCl2 preferred for making alkyl chlorides from alcohols?Primary alcohols react with HCl to give alkyl chlorides in presence of?What is the reactivity order of alcohols with a given halogen acid?Good yields of alkyl iodides come from heating alcohols with which mixture?Phosphorus tribromide is usually generated in situ from which reactants?Why can phenols not be turned into aryl halides like alcohols can?What is the main drawback of free radical chlorination of alkanes?Propene adds HBr by Markovnikov's rule. What is the major product?Discharge of bromine's reddish brown colour in CCl4 detects what?Alkyl bromide heated with NaI in dry acetone gives alkyl iodide. Name it.What drives the Finkelstein reaction forward?The Swarts reaction makes alkyl fluorides using which reagents?Iodination of benzene needs which added reagent to proceed?A benzene diazonium salt gives chlorobenzene when mixed with what?Iodobenzene is made from a diazonium salt by shaking it with what?Why do alkyl iodides boil higher than alkyl chlorides?Which C4H9Br isomer has the lowest boiling point?Why are haloalkanes only very slightly soluble in water?A haloalkane reacts with KCN. What is the main product?Why does AgCN give mainly isocyanides with haloalkanes?Nitrite ion attacking a haloalkane through nitrogen gives what?What order of kinetics does CH3Cl with hydroxide ion follow?How many steps does an SN2 reaction take?What is the SN2 reactivity order of alkyl halides?What intermediate forms in the slow step of an SN1 reaction?Which bromide reacts fastest by the SN1 mechanism?A dextrorotatory compound rotates plane polarised light in which way?In which year did Van't Hoff and Le Bel propose the tetrahedral carbon?Which of these molecules is achiral?What is the net optical rotation of a racemic mixture?Optically active 2-bromobutane is hydrolysed by SN1. What forms?(-)-2-Bromooctane reacts with NaOH by SN2. What is the product?A haloalkane heated with alcoholic KOH mainly gives what?By Zaitsev's rule, which alkene is the preferred elimination product?2-Bromopentane with alcoholic KOH gives which major product?A bulky base meets an alkyl halide with beta hydrogens. What is favoured?Grignard reagents are made by reacting haloalkanes with what?Why must even traces of moisture be kept away from a Grignard reagent?Bromoethane reacts with sodium in dry ether. Which alkane forms?An alkyl halide and an aryl halide with sodium in dry ether give an alkylarene. Name it.Resonance makes aryl halides unreactive to nucleophiles. How?What is the approximate C-Cl bond length in a haloarene?Why is the SN1 mechanism ruled out for haloarenes?Chlorobenzene is turned into phenol with aqueous NaOH under which conditions?A nitro group at which position has no effect on haloarene reactivity?In electrophilic substitution, a halogen on benzene behaves as what?In chlorobenzene, which effect controls where a new group enters?Which polyhalogen compound is widely used as a paint remover?Chloroform slowly oxidises in air and light to which poisonous gas?Iodoform's antiseptic action is actually due to what?Freons are chlorofluorocarbons of which hydrocarbons?What is the molecular formula of Freon 12?Many fluoroalkanes boil lower than their non-fluorinated analogues. Why?The ozone-depleting ability of CFCs arises from what?Geminal dihalides treated with strong bases can give which species?Haloalkanes react with lithium metal to give what?A reaction keeps its configuration at a stereocentre when which holds?Haloalkanes heated with aqueous hydroxide mainly undergo what?Haloalkanes react with ammonia to give which compounds?Which compound is a popular methylating agent in organic synthesis?DDT builds up in animals mainly in which tissue?Which haloalkane class has largely replaced CFCs as refrigerants?A halogen on an sp3 carbon next to a C=C bond makes which class of halide?In which class of halide is the halogen bonded to an sp2 carbon of a C=C bond?A halogen on an sp3 carbon attached to a benzene ring gives which class?Two halogens on the same carbon atom of a chain make which kind of dihalide?Common names call a vic-dihalide by which term?Why is thionyl chloride preferred for converting alcohols into alkyl chlorides?What observation shows an alkene reacting with bromine in CCl4?Which catalyst is typically used to chlorinate benzene to chlorobenzene?Without any copper salt, which reagent turns a diazonium salt into an aryl iodide?For the same alkyl group, how do boiling points of alkyl halides vary?Which of these haloalkanes is a gas at room temperature?What happens to alkyl bromides and iodides when exposed to light?