Question

Describe an expression for the corrosion rate of materials. Describe the importance of this expression to the design of structures. Name the different methods of protecting structures from uniform corrosion. Consider a copper-zinc corrosion couple. If the current density at the copper cathode is 0.05A/cm2, calculate the weight loss of zinc per hour if (a) the copper area is 100 cm and the zinc anode area is 1cm and (b) the copper cathode area is 1cm2 and the zinc anode area is 100cm. Hint: The current density in the cell is the same everywhere in the corrosion couple and zinc loses 2 electrons for each mole of zinc. Explain the importance of anodising treatment for aluminium. In steel reinforced concrete structures near water the steel reinforcement corrodes and the concrete surrounding generally cracks. Why the reinforced concrete be repaired in some cases? es this happen and how can

Answer 1

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