Chapter 8, Problem 4STP

Interpretation Introduction

Interpretation: The substance containing both covalent and ionic bonds needs to be identified.

Concept Introduction: When two or more atoms interact with each other, a chemical bond can form between them. There are two types of bonds; ionic and covalent depending on the type of atoms involved in bonding. If there is a huge electronegativity difference between two atoms, an ionic bond is formed between them and if two atoms have comparable electronegativity values, a covalent bond is formed.

Answer to Problem 4STP

Option (A)

Explanation of Solution

Reason for the correct option:

Consider option (A), the given substance is ${\text{NH}}_{\text{4}}{\text{NO}}_{\text{3}}$ . Here, one N atom is bonded with 4 H atoms, and 1 N atom is bonded with 3 O atoms. This is an ionic compound that is formed between ammonium ions ${\text{NH}}_4^{+}$ and nitrate ion ${\text{NO}}_3^{-}$ . Thus, there is an ionic bond in the substance. Also, the bond formed between the N atom and H atoms also between the N atom and O atoms is covalent in nature (formed by sharing of electrons). Thus, this substance contains bond covalent and ionic bonds.

Conclusion

Reason for incorrect option:

Consider option (B), ${\text{CH}}_{\text{3}}{\text{OCH}}_{\text{3}}$ . In this substance, there are only covalent bonds formed between C, O, and H atoms.

Consider option (C), LiF. There is an ionic bond between Li and F atoms. Here, F is more electronegative than Li.

Consider option (D) CaCl₂. There is an ionic bond between Ca and Cl atoms. Here, Cl is more electronegative than Ca.

Therefore, options (B), (C), and (D) are incorrect options.