A byproduct of hydrogen fuel cell operation includes water.

A byproduct of hydrogen fuel cell operation includes water.

• A. Water
• B. Carbon dioxide
• C. Methane
• D. Nitrogen

Answer: (A)

Hydrogen fuel cells turn the chemical energy of hydrogen and oxygen into electricity, and the byproduct of that reaction is water. In the typical operation, hydrogen at the anode is oxidized and, at the cathode, oxygen from the air combines with protons and electrons to form water. The overall reaction is 2 H2 plus O2 yielding 2 H2O. Because the process uses hydrogen as the fuel and oxygen as the oxidizer, water is the only stable byproduct under normal operating conditions, unlike carbon dioxide, methane, or nitrogen, which would come from burning hydrocarbons or other processes. Keep in mind that the water can emerge as liquid or vapor depending on the cell’s temperature and humidity, and managing it is part of keeping the fuel cell efficient.

Hydrogen fuel cells turn the chemical energy of hydrogen and oxygen into electricity, and the byproduct of that reaction is water. In the typical operation, hydrogen at the anode is oxidized and, at the cathode, oxygen from the air combines with protons and electrons to form water. The overall reaction is 2 H2 plus O2 yielding 2 H2O. Because the process uses hydrogen as the fuel and oxygen as the oxidizer, water is the only stable byproduct under normal operating conditions, unlike carbon dioxide, methane, or nitrogen, which would come from burning hydrocarbons or other processes. Keep in mind that the water can emerge as liquid or vapor depending on the cell’s temperature and humidity, and managing it is part of keeping the fuel cell efficient.