2. Pourbaix diagrams illustrate the chemical thermodynamic information of a system. Figure 2 presents the Pourbaix diagram for the iron-water system. 1 Fe Fe? Fe,0 E vs. SHE/V Fe, -1- Fe -2 0 2 4 6 8 10 12 14 pH Figure 2. Pourbaix diagram for an iron-water system (a) Give balanced equations to show the pure redox and pure acid-base reactions observed in the diagram. (6 marks) (b) What form of iron would be predominant in a neutral solution at a potential of 0.00 V? (1 mark) (c) Read a value for the standard reduction potential for the reduction of Fe2+ to Fe metal. (2 marks) (d) Pourbaix diagrams illustrate the chemical thermodynamic information of a system. Explain why it is not possible to predict the rate at which a corrosion reaction will proceeds using such diagrams. (5 marks) (e) Under the right conditions, some metals such as iron can form a protective layer that impedes further corrosion. (i) What is this phenomenon called? (1 mark) (ii) How will this layer affect polarization? (3 mark (iii) Explain how this layer may be broken down and what this could potentially lead to. (3 mark (iv) This protective layer can be electrically conductive or insulative. Which in your opinion is the best at protecting the underlying metal from corrosion, and why? (4 mark