What is an electrolyte?

• A. A protective coating
• B. A moist solution that allows ion movement and enables redox reactions
• C. Water containing no ions
• D. A material that never conducts electricity

Answer: (B)

An electrolyte is the moist conductive medium that contains ions and allows them to move, letting the chemical reactions at the electrodes balance and proceed. In corrosion, the metal’s surface acts as an anode and cathode in an electrochemical cell, and the electrons travel through the metal while the ions move through the electrolyte to maintain charge balance. Pure water without ions wouldn’t conduct well, and a protective coating or a material that never conducts electricity won’t support those needed ion movements. So a moist, ion-containing solution that enables redox reactions is the correct description of an electrolyte.