What overall reaction occurs in a hydrogen-oxygen fuel cell?

In a hydrogen-oxygen fuel cell, the overall reaction is represented by the equation 2H2 + O2 → 2H2O. This equation illustrates how hydrogen gas and oxygen gas chemically react to form water.

In a fuel cell, hydrogen is oxidized, releasing electrons and resulting in the production of protons. Meanwhile, oxygen molecules serve as oxidizing agents, accepting the electrons and thus reducing to form water. The stoichiometry of the balanced equation showcases that two molecules of hydrogen gas react with one molecule of oxygen gas to produce two molecules of water. This reaction emphasizes the fundamental principles of conservation of mass and charge, which are central to electrochemical processes.

Understanding this reaction is crucial because one of the primary functions of a fuel cell is to convert chemical energy into electrical energy efficiently and sustainably, with water being the only byproduct. This highlights the appeal of hydrogen fuel cells in renewable energy technologies. Other options do not accurately reflect the stoichiometry of the reaction in a fuel cell context, thus leading to incorrect representations of the overall chemical process.