Alcohol Phenol And Ethers

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Step 1: Protonation of alkene due to the presence of double bond which  attacks the H₃O⁺ ion and forms carbocation. 

Step 2: Water molecule act as nucleophile and attack the carbocation. 

Step 3: Deprotonation occur to get the alcohol and hydronium ion forms 

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The C-OH bond in phenols has double bond character due to resonance  of electron pairs of oxygen atom with the pi electrons of phenyl ring, which makes the C-OH bond strong and hence, the  nucleophilic substitution of a nucleophile with the -OH group of alcohol is not possible as the C-OH does not break easily.

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The electron pairs of oxygen atom of hydroxyl (-OH) group  in phenols are in conjugation with the pi electrons of phenyl ring and hence, the bond C-OH bond has double bond character due to which OH group in phenols more strongly held as compared to OH group in alcohols.

Resonance in phenol

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The propan-2-one can be converted into tert-butyl alcohol by using CH₃MgBr grignard reagent to form the additional product tert-butyl alcohol.

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The enzyme invertase, which is present in yeast,   is used to convert sucrose to glucose and fructose. The glucose and fructose are further converted to ethanol by zymase enzyme (also present in yeast).

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The decreasing order of acidity:

H₂O > ROH >  HC ≡ CH 

The more the stability of the conjugate base of the given compounds, the more acidity will be.

^? OH > ^? O-R > ^? C ≡ CH 

The negative charge on the electronegative oxygen atom is more stable than carbon atom. The + I effect of the alkyl group does not stabilize the negative charge on the electronegative oxygen atom, hence less stable than ^? OH. 

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When benzene diazonium chloride is heated with water, it forms phenol along with nitrogen and hydrochloric acid as by-products as shown below:

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The decreasing order of reactivity of alcohol with sodium metal:

Tertiary Alcohols > Secondary Alcohols   > Primary Alcohols 

When alcohol reacts with active metals  e.g. Na. K etc., the O-H bond of alcohols breaks to form the corresponding alkoxide. The alkyl  group is electron donating and has +I effect due to which the O-H bond becomes strong and hence, the reactivity of alcohol decreases.

Fig: +I effect of alkyl group of alcohol

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The increasing order of acidity:

o-cresol  <  Phenol   <  o-nitrophenol

The electron-withdrawing group on the substituted phenol increases the acidity due to increasing the polarity of the O-H bond and thus, the acidity increases  and vice versa. -NO₂ is an electron-withdrawing group whereas the -CH₃ group is an electron-donating group.