CBSE Class 12 (Science) Alcohols, Phenols and Ethers — practice questions
94 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 12 (Science) Alcohols, Phenols and Ethers in the app →Phenol is more acidic than ethanol because:The Williamson ether synthesis works best with:An ALCOHOL in which the $\mathrm{-OH}$ group is attached to a carbon bonded to ONE other alkyl group is classiThe IUPAC name of $\mathrm{(CH_3)_2CHOH}$ isThe reaction of ethanol with sodium metal producesThe acidity (Brønsted acidity) order of the following isEthanol heated with concentrated $\mathrm{H_2SO_4}$ at $443\,\text{K}$ (170°C) gives mainlyThe WILLIAMSON ETHER SYNTHESIS prepares ethers by reactingThe REIMER-TIEMANN reaction converts phenol to salicylaldehyde. The reagents arePhenol reacts with bromine WATER (aqueous $\mathrm{Br_2}$) at room temperature to giveEthanol reacts with $\mathrm{PCl_5}$ to give which set of products?The KOLBE reaction converts phenol (in the form of sodium phenoxide) into salicylic acid. The conditions and kWhich compound is also known by the name carbolic acid?From which natural material was phenol first isolated?In phenol, the hydroxyl group is attached to carbon of which system?Ethers can be viewed as derived from an alcohol by what change?In an allylic alcohol, the OH is on an sp3 carbon placed where?A benzylic alcohol has its OH on an sp3 carbon next to what?In a vinylic alcohol such as CH2=CH-OH, the OH is bonded to which carbon?What is the C-O bond length in phenol?The C-O bond length in ethers is nearly what value?Why is the C-O-C angle in ethers slightly above the tetrahedral angle?Why is the C-O bond in phenol shorter than in methanol?Acid catalysed hydration of an unsymmetrical alkene follows which rule?What is the first step in acid catalysed hydration of an alkene?Hydroboration-oxidation of propene mainly gives which product?Which reagent adds to alkenes to give trialkylboranes?Reduction of an aldehyde such as ethanal yields which alcohol type?Which metal is a usual catalyst for hydrogenating aldehydes to alcohols?Commercially, acids are reduced to alcohols after first being converted to what?A Grignard reagent reacting with methanal gives which type of alcohol?Propanone with methylmagnesium bromide, then hydrolysis, gives which type of alcohol?What is the first step of a Grignard reaction with a carbonyl compound?At what temperature is chlorobenzene fused with NaOH to make phenol?Which reagent is used to sulphonate benzene before fusion with NaOH?Which temperature range is used to make a diazonium salt from an aromatic amine?Which useful by-product forms along with phenol in the cumene process?Cumene, the starting material for industrial phenol, is also called what?Boiling points of alcohols rise with carbon number because of what?Branching in the carbon chain of an alcohol does what to its boiling point?Why do alcohols boil higher than ethers of similar molar mass?Methoxymethane boils at a temperature relative to ethanol and propane that is what?Which has the highest boiling point: n-butane, ethoxyethane, pentanal, pentan-1-ol?Among ethanol, propan-1-ol, butan-1-ol and pentan-1-ol, which boils lowest?Protonated alcohols react as which type of species?Which gas is released when ethanol reacts with sodium metal?Phenols are stronger acids than which pair of compounds?Alcohols act as Bronsted acids because they can do what?Which has the highest acid strength: methanol, ethanol, propan-2-ol, tert-butanol?Which is the stronger base: sodium ethoxide or sodium hydroxide?Compared with phenol, ortho and para nitrophenols are what?Which alcohol type gives turbidity immediately with Lucas reagent?At room temperature, primary alcohols with Lucas reagent show what?Alcohols are converted to alkyl bromides by which reagent?Which reagent dehydrates an alcohol to an alkene?Which alcohol type dehydrates most easily?At which temperature does ethanol with H2SO4 give ethene?Which step is the slowest in dehydration of ethanol?Acidified KMnO4 oxidises a primary alcohol directly to what?Which reagent oxidises primary alcohols to aldehydes in good yield?Oxidation of a secondary alcohol with chromic anhydride gives what?Which type of alcohol resists oxidation under mild conditions?Oxidation of alcohols is also known as what type of reaction?In the body, methanol is oxidised first to methanal and then to what?How is a methanol poisoned patient treated?In phenol, the -OH group directs an incoming electrophile to which positions?Phenol with dilute nitric acid at 298 K gives what?Why is o-nitrophenol steam volatile?Concentrated nitric acid converts phenol into what?Phenol with bromine water gives which white precipitate?Phenol brominates without FeBr3 because of what?Sodium phenoxide heated with CO2 mainly gives which acid?Why is phenoxide more reactive than phenol toward electrophiles?Phenol with chloroform and NaOH introduces which group at the ortho position?Heating phenol with zinc dust gives which product?How was methanol, called wood spirit, originally produced?Methanol is a colourless liquid boiling at what temperature?What is the boiling point of ethanol?Which yeast enzyme converts glucose and fructose to ethanol?Fermentation of sugars to ethanol requires which conditions?Zymase action stops once alcohol exceeds what percentage?If air enters a fermenting mixture, ethanol is oxidised to what?Which foul smelling liquid is added to denature commercial alcohol?Bimolecular dehydration of alcohols to ethers follows which mechanism?Dehydration of alcohols to ethers works best for which alkyl groups?Sodium methoxide with tert-butyl bromide gives mainly what?Why do alkoxides cause elimination with tertiary alkyl halides?For ether synthesis from an alkoxide, the alkyl halide should be what?The boiling points of ethers are close to those of which compounds?Why is ethoxyethane miscible with water to an extent like butan-1-ol?Ethers rank how in reactivity among functional groups?Which hydrogen halide cleaves ethers most readily?Alkyl aryl ethers cleave with HX at which bond?What shape describes the electron pairs around oxygen in ethers?