Page 27 - Fuel Cell Student Edition

Gl o ss ar y

ANION a negatively charged ion

ANODE the electrode to which electrons flow (negative terminal)

ATOM the basic unit of an element

CATION a positively charged ion

CATHODE the electrode from which electrons flow (positive terminal)

CHEMICAL a description of a chemical reaction in the form of an equation showing the
EQUATION reactants and products

CHEMICAL a state in which both reactants and products of a reaction are present at
EQUILIBRIUM concentrations which have no further tendency to change over time; a
stable mixture of reactants and products

COEFFICIENT a multiplicative factor in an expression, often a constant

CORRODE to damage or destroy metal by oxidation

ELECTROLYSIS using direct current to drive a chemical reaction, such as splitting water into
hydrogen and oxygen

ELECTROLYTE a liquid or gel that contains ions and can be decomposed by electrolysis

FORWARD REACTION a chemical reaction where the reactants on the left side of the equation
react to form the product on the right side of the equation

26 TOTAL REDOX™ – FUEL CELLS TOTAL REDOX™ – FUEL CELLS 27