Question

Assertion (A): Alcohols act as Bronsted bases as well as Bronsted acids.
Reason (R): Alcohols react as both nucleophiles and electrophiles.

• A. Both A and R are true and R is the correct explanation of A.
• B. Both A and R are true but R is not the correct explanation of A.
• C. A is true but R is false.
• D. A is false but R is true.

Hint:

Alcohols as Bronsted acid: $ROH \rightarrow RO^- + H^+$. As Bronsted base: $ROH + H^+ \rightarrow ROH_2^+$. This is proton behavior, not nucleophilicity.

Answer 1

The Correct Option is B

Step 1: Check the Assertion.
Alcohols can donate a proton from the $-OH$ group (Bronsted acid, forming alkoxide ions) and can accept a proton on the oxygen lone pair (Bronsted base). The Assertion is TRUE.
Step 2: Check the Reason.
Alcohols do act as nucleophiles (via oxygen lone pairs) and occasionally as electrophiles. The Reason is TRUE.
Step 3: Does R explain A?
Bronsted acid-base behaviour (proton donation/acceptance) is not the same as nucleophile/electrophile behaviour (electron pair donation in bond formation). The amphoteric Bronsted character of alcohols arises from the polarity of the O-H bond and oxygen lone pairs, not from nucleophilicity/electrophilicity per se. Hence R does NOT correctly explain A.
Step 4: Conclusion.
Both A and R are true, but R is not the correct explanation of A.
\[ \boxed{\text{Both true; R not the correct explanation}} \]