How many grams of Fe(s) are lost in 1.0 h if a current of 0.50 A runs through the hull? — Electrochemistry Chemistry Question

💡 Solution & Explanation

**Step 1: Calculate total charge passed.** $$Q = I \times t = 0.50\ \text{A} \times 3600\ \text{s} = 1800\ \text{C}$$ **Step 2: Find moles of electrons transferred.** $$n_{e^-} = \frac{Q}{F} = \frac{1800}{96500} = 0.01865\ \text{mol}$$ **Step 3: Apply Faraday's law to find moles of Fe dissolved.** The anodic dissolution of iron: $$\ce{Fe(s) -> Fe^{2+}(aq) + 2e-}$$ Each mole of Fe requires 2 moles of electrons: $$n_{\text{Fe}} = \frac{n_{e^-}}{2} = \frac{0.01865}{2} = 0.009326\ \text{mol}$$ **Step 4: Convert to mass.** $$m_{\text{Fe}} = n_{\text{Fe}} \times M_{\text{Fe}} = 0.009326 \times 55.85 = 0.521\ \text{g} \approx \mathbf{0.522\ \text{g}}$$ $$\boxed{\text{Answer: B — } 0.522\ \text{g of Fe is lost}}$$