Assertion (A): Alcohols act as Bronsted bases as well as Bronsted acids.
Reason (R): Alcohols react as both nucleophiles and electrophiles.
Reason (R): Alcohols react as both nucleophiles and electrophiles.
Show Hint
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
The Correct Option is B
Solution and Explanation
Bronsted acid-base theory: an acid donates a proton ($H^+$), a base accepts a proton.
Step 2: Analysis
Assertion is true: alcohols can donate the $-$OH proton (acting as Bronsted acids, forming alkoxide ions) and can also accept a proton on the oxygen lone pair (acting as Bronsted bases). Reason is also true: alcohols can act as nucleophiles (lone pairs on oxygen) and sometimes as electrophiles. However, the amphoteric Bronsted behavior of alcohols is due to the $-$OH group's ability to both donate and accept protons, not simply because they act as nucleophiles and electrophiles.
Step 3: Conclusion
Both statements are true, but the Reason does not correctly explain the Assertion.
Final Answer: (B)
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