Which one of the following solutions is not capable of conducting electricity?

Electrical conductivity in aqueous solutions depends on the presence of mobile ions. Electrolytes are substances that dissociate into ions when dissolved in water, allowing the flow of electricity. Sodium chloride (NaCl) is a strong electrolyte that dissociates completely into Na+ and Cl- ions. Similarly, copper sulphate (CuSO4) and sodium hydroxide (NaOH) are electrolytes that produce ions in solution, making them capable of conducting electricity. In contrast, sugar (sucrose) is a pure covalent compound [1]. When sugar dissolves in water, it undergoes dissolution but not dissociation; it remains as neutral molecules rather than breaking apart into ions [1]. Because there are no free-moving charged particles (ions) to carry the electrical current, an aqueous sugar solution is a non-electrolyte and is not capable of conducting electricity [1].

Sources

1. [1] https://www.aakash.ac.in/important-concepts/chemistry/electrolytes-and-non-electrolytes