Question

An ionic bond is formed when:
(A) the combining atoms gain electrons.
(B) the combining atoms lose electrons.
(C) a metallic element reacts with a nonmetallic element.
(D) two metallic elements react.

Answer 1

Hint: An ionic bond is formed by complete transfer of electrons from one atom to another atom. An ionic bond is present between oppositely charged ions, cations and anions.

Complete answer:
An ionic bond is also called an electrovalent bond. An ionic bond is the electrostatic force of attraction present between oppositely charged ions. Thus, when cation and anion come together, they attract each other. This electrostatic attraction between cation and anion is the ionic bond. An ionic bond is formed between atoms of different elements, having significant electronegativity difference. Thus, a highly electropositive metal such as sodium metal and highly electronegative non metal such as chlorine non metal combine to form an ionic bond. Sodium metal loses an electron to form sodium cation. Chlorine nonmetal gains this electron to form chloride anion. The electrostatic force of attraction between positively charged sodium cation and negatively charged chloride anion is the ionic bond.
$Na\to Na^+ + e^-$
$Cl + e^- \to Cl^-$
Overall reaction:
$Na + Cl \to NaCl$
An ionic bond is formed when a metallic element reacts with a non-metallic element

Hence, the correct option is the option (C).

Note: A covalent bond formed between two atoms has little (or no) electronegativity difference. Thus, when two atoms of the same element such as two chlorine atoms combine, they form a covalent bond. A covalent bond is formed by sharing of electrons between two atoms. A covalent bond can be either pure covalent or covalent bond with partial ionic character. A pure covalent bond is formed when two atoms have the same electronegativity, i.e, two atoms are of the same element. A covalent bond with partial ionic character is obtained when two atoms have some electronegativity difference.