(a) It has been reported, that acid rain with a pH of 3.5 could corrode mild steel. Write a chemical equation that describes the attack of acid rain on an iron (Fe) material. (b) If the iron material were covered with a surface layer of copper, would this help to stop the effects of acid rain? Explain.

Acid rain is formed when sulfur dioxide (SO2) and nitrogen oxides (NOx) are released into the atmosphere and react with water, oxygen, and other chemicals to form sulfuric and nitric acids. The pH of the acid rain given in the problem is 3.5. We will focus on the reaction between iron and sulfuric acid for this exercise. Here is the chemical equation representing the reaction between iron (Fe) and sulfuric acid (H2SO4): Fe(s) + H2SO4(aq) -> FeSO4(aq) + H2(g) To balance this equation, we can see that there is already 1 Fe atom, 1 H2SO4 molecule, 1 FeSO4 molecule, and 1 H2 molecule on each side of the equation, so the equation is balanced.

To answer this question, we need to consider the electrochemical series. Metals such as copper and iron possess varying tendencies to you lose or gain electrons. Metals that are more likely to lose electrons (and hence corrode more easily) have a lower position in the electrochemical table compared to metals that have a higher position. Copper is less reactive than iron and has a higher position in the electrochemical series. This means that copper is slower to corrode and would require stronger acids to initiate the corrosion process. Furthermore, copper can serve as a barrier between the acid rain and the iron, slowing down the rate of corrosion of the iron material. However, if there are defects or cracks in the copper layer, the acid rain can still come into contact with the iron material, leading to its corrosion. Additionally, if there is a galvanic cell formed between the copper and iron material, it may result in promoting the corrosion of the iron. In conclusion, covering iron material with copper may help reduce the corrosion of the iron by acid rain. However, the protection is not absolute, as defects in the copper layer and the formation of a galvanic cell can still result in the iron corroding. It is important to ensure proper coverage, and other methods like protective coatings or galvanizing may be more effective in preventing corrosion.