Question

What are some examples of Lewis acids and bases?

Answer 1

Lewis’s acids are electrophilic i.e. they attract and accept electron pairs whereas, Lewis’s bases are nucleophilic i.e. they donate electron pairs or attack a positive charge with their lone pair of electrons.

Complete answer:
Let us know about the Lewis’s acids and bases in detail;
Lewis’s acid is the chemical species which has an empty orbital which is factually capable of accepting two electrons i.e. an electron pair. For example;
The proton $\left( {{H}^{+}} \right)$ .
Acidic compounds such as $N{{H}_{4}}^{+}$ and ${{H}_{3}}{{O}^{+}}$ .
Transition metal cations with high oxidation state such as $F{{e}^{3+}}$ .
Phosphorus pentahalide, arsenic pentahalide and antimony pentahalide.
Trigonal planar species $\left( B{{F}_{3}} \right)$ .
Enones and tetracyanoethylenes (electron poor $\pi$ - system)
Lewis’s base is the chemical species which has a filled orbital containing two electrons i.e. an electron pair which needs to be donated. For example;
Anions such as ${{H}^{-}}$ and ${{F}^{-}}$ (simple), sulphate (complex)
Compounds of O, S, Se and Te in oxidation state of 2 (water, ethers and ketones).
Ethyne, ethene and benzene (electron rich $\pi$ - system).
Amines $\left( N{{H}_{3-x}}{{R}_{x}} \right)$ in which R is alkyl or aryl.

Note:
The Lewis’s acids and bases react with each other as one will accept the electron and other will donate so that reaction will continue and bonds will form. The common applications of the same are;
Formation of the ligands.
Production of chelating agents.
Modification of the metallic catalyst.
In Friedel – Crafts alkylation.