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Assertion : Alcohols and water are wea...

Assertion : Alcohols and water are weaker acids than phenols.
Reason : The delocalisation of negative charge makes the phenoxide ion more stable and favour the ionisation of phenol.

A

If both (A) and (R) are correct and (R) is the correct explanation of (A).

B

If both (A) and (R) are correct, but (R) is not the correct explanation of (A)

C

If (A) is correct, but (R) is incorrect

D

If both (A) and (R) are incorrect.

Text Solution

Verified by Experts

The correct Answer is:
A

The reaction of phenol with aqueous NaOH indicates that phenols are stronger acids than alcohols and water. Due to the higher electronegativity of `sp^2` hybridised carbon ofphenol to which OH is attached, electron density decreases on oxygen. This increases the polarity of OH bond and results in an increase. in ionisation of phenols than that of alcohols. In alkoxide ion, the negative.charge is localised on oxygen while in phenoxide ion, the charge is delocalised. The delocalisation of negative charge makes phenox - ide ion more stable and favours the ionisation of phenol.
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BRILLIANT PUBLICATION-ALCOHOL, PHENOL & ETHER -LEVEL II (ASSERTION - REASON TYPE)
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  5. Assertion : The cleavage of C-O bond in ethers takes place under dra...

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  7. Assertion: Neopentyl alcohol on treatment with HCl gives neopentyl chl...

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  8. Assertion: Phenoxide ion on treatment with an active alkyl h...

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  9. Assertion:Phenol forms 2,4,6-tribromophenol on treatment with Br2 in c...

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  10. Assertion: Alcohols have higher boiling points than ethers of comparab...

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  11. Assertion: Commercially carboxylic acids are reduced to alcohols by co...

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  13. Assertion: CO2 is non polar, while ROR is polar in nature. Reason: ...

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  14. Assertion: t-Butyl methyl ether is not prepared by the reaction of t-b...

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  15. Assertion: Anisole undergoes electrophilic substitution at o-and p-pos...

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  18. Assertion: Solubility of n-alcohl in water decreases with increase in ...

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  19. Assertion: The bond angle in alcohols is slightly less than the tetr...

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