In a standard lead-acid battery, electrolyte consists of water and which acid?

In a standard lead-acid battery, electrolyte consists of water and which acid?

• A. Hydrochloric acid
• B. Nitric acid
• C. Sulfuric acid
• D. Acetic acid

Answer: (C)

The electrolyte in a standard lead-acid battery is water mixed with sulfuric acid. The sulfuric acid provides sulfate ions that participate in the chemical reactions at the electrodes and also enables ion conduction through the solution. As the battery discharges, the reactions on the anode and cathode form lead sulfate on both electrodes and water is produced, which reduces the acid concentration and makes the electrolyte more dilute. When you recharge, the reverse reactions regenerates the sulfate and restores the acid concentration. Sulfuric acid is the right choice because it supplies the necessary sulfate ions and supports reversible, efficient chemistry with lead and lead dioxide; other acids would either corrode the lead, release unwanted gases, or not supply the needed sulfate ions, leading to poor performance or damage.

The electrolyte in a standard lead-acid battery is water mixed with sulfuric acid. The sulfuric acid provides sulfate ions that participate in the chemical reactions at the electrodes and also enables ion conduction through the solution. As the battery discharges, the reactions on the anode and cathode form lead sulfate on both electrodes and water is produced, which reduces the acid concentration and makes the electrolyte more dilute. When you recharge, the reverse reactions regenerates the sulfate and restores the acid concentration. Sulfuric acid is the right choice because it supplies the necessary sulfate ions and supports reversible, efficient chemistry with lead and lead dioxide; other acids would either corrode the lead, release unwanted gases, or not supply the needed sulfate ions, leading to poor performance or damage.