What is a Pourbaix diagram and what information does it convey?

• A. A pH–potential stability diagram showing immune, corroding, or passive regions and the predominant species at given pH and E.
• B. A plot of current versus time for corrosion testing.
• C. A phase diagram of metal alloys at elevated temperature.
• D. A chart of diffusion coefficients as a function of pH.

Answer: (A)