Groundwater Often Has Low Levels of Dissolved Oxygen Because It $\rightarrow$

question 84

Multiple Choice

Groundwater often has low levels of dissolved oxygen because it is not continually exposed to the atmosphere. When groundwater reaches the surface, the following reaction involving soluble iron(II) can occur. What are the oxidation numbers of the elements in the product, Fe(OH) ₃?
4Fe²⁺(aq) + O₂(g) + 2H₂O(l) $\rightarrow$ 8OH^- $\rightarrow$ Fe(OH) ₃(s)

• A) Fe = +2, O = -2, H = 0
• B) Fe = +2, O = -1, H = -1
• C) Fe = +4, O = -2, H = +1
• D) Fe = +3, O = -1, H = +1
• E) Fe = +3, O = -2, H = +1

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