CBSE Class 12 (Science) Haloalkanes and Haloarenes — practice questions
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Practice CBSE 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 withA 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?Which general formula fits the homologous series of simple alkyl halides?What is the IUPAC name of neopentyl bromide, (CH3)3CCH2Br?Allyl bromide, CH2=CHCH2Br, has which IUPAC name?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?Which catalyst is needed when HCl reacts with primary or secondary alcohols?What is the order of reactivity of alcohols toward a given halogen acid?Which reagent set converts an alcohol into an alkyl iodide in good yield?Why do usual alcohol methods fail to make aryl halides from phenols?What is the main drawback of free radical halogenation of alkanes?Propene reacts with HBr to give mainly which product?What observation shows an alkene reacting with bromine in CCl4?Alkyl iodides are prepared from alkyl chlorides or bromides by which reaction?Why does precipitation of NaCl or NaBr help the Finkelstein reaction?Which compound is used in the Swarts reaction to make alkyl fluorides?Which catalyst is typically used to chlorinate benzene to chlorobenzene?Why is nitric acid present when benzene is iodinated?Why is fluorobenzene not made by direct halogenation of benzene?Which reagent replaces a diazonium group by -Cl or -Br in the Sandmeyer reaction?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?Why do para-dihalobenzenes melt higher than the ortho and meta isomers?Which organohalogen derivatives are generally heavier than water?Which of these haloalkanes is a gas at room temperature?What happens to alkyl bromides and iodides when exposed to light?What are electron-rich species that attack electron-deficient centres called?Which pair are ambident nucleophiles?Which main product forms when a haloalkane is heated with silver cyanide?Why does AgCN give isocyanides while KCN gives cyanides?The SN2 hydrolysis of chloromethane follows which order of kinetics?In an SN2 reaction, how do bond breaking and bond making occur?An SN2 reaction at a chiral carbon leads to which stereochemical result?Which halide reacts fastest in SN2 reactions?What is the slow step in SN1 hydrolysis of tert-butyl bromide?Which type of solvent generally favours SN1 reactions?The rate of an SN1 reaction depends on the concentration of what?Why do allylic and benzylic halides react readily by SN1?Which halide ion is the best leaving group?What does a polarimeter measure?A compound rotating plane polarised light clockwise is called what?Which scientist observed in 1848 that crystals exist as mirror images?Van't Hoff and Le Bel argued in 1874 that the four valencies of carbon are arranged how?A carbon bearing four different groups is called what?Which of these compounds is chiral?What does the term enantiomers describe?Which property differs between two enantiomers?An equal mixture of two enantiomers is called what?Why is a racemic mixture optically inactive?Preservation of spatial arrangement at a stereocentre during a reaction is called what?Why does SN1 at a chiral carbon lead to racemisation?SN1 reactions of optically active halides give which outcome?Heating a haloalkane having a beta hydrogen with alcoholic KOH causes what?Which rule predicts the major alkene in dehydrohalogenation?Who formulated the elimination rule for the more substituted alkene in 1875?In which year were Grignard reagents first reported?What is the general formula of a Grignard reagent?Why must Grignard reagents be made under anhydrous conditions?An alkyl halide and an aryl halide with sodium in dry ether form an alkylarene. What is this reaction?Two aryl halide molecules with sodium in dry ether give a biaryl. What is this called?Where does a halogen on a benzene ring direct an incoming electrophile?Why do halogens deactivate the benzene ring despite being o,p-directing?What are carbon compounds with more than one halogen atom collectively called?Which polyhalogen compound is widely used as a paint remover and aerosol propellant?Chloroform slowly oxidises in air and light to which poisonous gas?Why is chloroform stored in closed dark coloured bottles?Chloroform today is mainly used to make which refrigerant?Which compound was once used as a spot remover and fire extinguisher fluid and harms ozone?Why was iodoform used as an antiseptic?Chlorofluorocarbons of methane and ethane are collectively known as what?What is the formula of Freon 12?Freon 12 is manufactured from which compound by the Swarts reaction?Who discovered the insecticidal effectiveness of DDT in 1939?Paul Muller received the 1948 Nobel Prize in which field for the DDT discovery?Where does DDT accumulate in animals?Which compound was the first chlorinated organic insecticide?Chloroform was once used in surgery for what medical purpose?What charge distribution does the polar C-X bond of an alkyl halide have?Methylene chloride is another name for which compound?