Chapter U1, Problem 19STP

Interpretation Introduction

Interpretation:

The substance that conducts electricity needs to be determined from the given options.

Concept introduction:

On the basis of chemical bonding, compounds can be classified as ionic and covalent compounds. Ionic compounds have electrostatic force of attraction between cation and anions.

Covalent compounds are formed by equal sharing of electrons between bonded atoms. Ionic compounds are good conductor of electricity due to presence of ions whereas covalent compounds are insulators.

Answer to Problem 19STP

Option (B) and (C) are correct options.

Explanation of Solution

Reason for correct option: Ionic compounds are good conductor of electricity in their aqueous state but they act as insulator in solid state. This is because in solid state, ions are strongly bonded with each other. ${\text{Cu(NO}}_{\text{3}}{\text{)}}_{\text{2(aq)}}$ and ${\text{NaOH}}_{\text{(aq)}}$, both can form ions as they are in aqueous state therefore they are good conductors of electricity.

Conclusion

Reasons for incorrect options:

${\text{NO}}_{\text{2(g)}}$ and ${\text{Cu(OH)}}_{\text{2(s)}}$ cannot conduct electricity because ${\text{NO}}_{\text{2(g)}}$ is a covalent compound which cannot form ions. ${\text{Cu(OH)}}_{\text{2(s)}}$ is in solid state therefore it cannot form ions and act as insulator.