Question

Which activity from following is exhibited by Lewis base according to definition?

• A. accept a pair of electron
• B. donate a pair of electron
• C. accept $H^{+}$ ions
• D. donate OH ions

Hint:

Chemistry Tip: Mnemonic: Lewis Acid = Acceptor. Lewis Base = Donor (like a "Base" that provides a foundation).

Answer 1

The Correct Option is B

Concept: Chemistry - Acids and Bases (Lewis Theory).

Step 1: Recall the Lewis theory of acids and bases. According to the theory proposed by G.N. Lewis, acid-base reactions are defined entirely by the transfer of electron pairs, without any requirement for hydrogen or hydroxide ions.

Step 2: Define a Lewis acid. A Lewis acid is defined as any chemical species that is electron-deficient and capable of accepting a pair of electrons to form a coordinate covalent bond.

Step 3: Define a Lewis base. Conversely, a Lewis base is defined as any chemical species that has at least one lone pair of electrons and is capable of donating this electron pair to a Lewis acid.

Step 4: Evaluate the given options against the definitions. Option (A) defines a Lewis acid. Option (C) defines a Brønsted-Lowry base (proton acceptor). Option (D) defines an Arrhenius base (hydroxide donor).

Step 5: Conclude the correct characteristic. Only Option (B), "donate a pair of electron", correctly matches the fundamental definition of a Lewis base. $$ \therefore \text{A Lewis base is an electron pair donor.} $$