A fuel cell functions by converting what type of energy into electrical energy?

A fuel cell operates by converting chemical energy directly into electrical energy through electrochemical reactions. In a typical fuel cell, hydrogen (or another fuel) reacts with an oxidizer, commonly oxygen, producing water and releasing electrical energy in the process. This reaction occurs in the presence of an electrolyte, which allows for the necessary ion transport while separating the reactants.

The conversion of chemical energy to electrical energy is highly efficient compared to other processes, such as combustion, which primarily generates thermal energy. Because of this, fuel cells are a popular choice for clean energy applications, producing minimal emissions while harnessing energy from chemical reactions. The core principle behind fuel cells is thus entrenched in the transformation of chemical energy stored in fuels into usable electrical energy, making this the correct answer.