Question

State the type of compounds formed by the transfer of valence electrons from one atom to another and explain the method of their formation. What is the role of ‘cations’ and ‘anions’ in their formation?

Answer 1

Compounds formed by the transfer of valence electrons from one atom to another are called ionic compounds (electrovalent compounds).

Method of formation: 

One atom, usually a metal, loses valence electrons to form a positively charged cation, while another atom, usually a non-metal, gains electrons to form a negatively charged anion. The electrostatic attraction between the cation and anion forms an ionic bond.

Role of cations and anions:

• Cations: Cations are positively charged ions formed when an atom loses one or more valence electrons. They provide the positive charge needed to form an ionic compound.
• Anions: Anions are negatively charged ions formed when an atom gains one or more valence electrons. They provide the negative charge needed to form an ionic compound.

Thus, cations and anions are held together by strong electrostatic attraction, forming an ionic compound.