Which of the following accounts for the difference in the mode of conduction of electricity by metals and aqueous salt solutions?

Answer Details

The difference in the mode of conduction of electricity by metals and aqueous salt solutions is due to the fact that metals have mobile electrons that can move freely and carry an electric current, while aqueous salt solutions have mobile ions (charged particles) that carry an electric current. Therefore, the correct option is: "Electricity is carried by mobile electrons in metals but by ions in aqueous salt solution." In metals, the outermost electrons of the atoms are not tightly bound to their nuclei, which allows them to move freely through the metal structure. When a voltage is applied, these mobile electrons can move in a particular direction, carrying an electric current. In contrast, aqueous salt solutions contain dissolved salts that break up into positively and negatively charged ions. When a voltage is applied, these mobile ions move towards the opposite electrode, carrying an electric current. Therefore, the mode of conduction of electricity in metals and aqueous salt solutions is fundamentally different, with metals conducting electricity via mobile electrons, and aqueous salt solutions conducting electricity via mobile ions.