Hydrazine (N2H4\text{N}_2\text{H}_4N2H4) is added to high-pressure steam systems in power stations to prevent the internal corrosion of iron-based alloy components. It reacts with dissolved oxygen according to the following equation:
N2H4+O2→N2+2H2O \text{N}_2\text{H}_4 + \text{O}_2 \rightarrow \text{N}_2 + 2\text{H}_2\text{O} N2H4+O2→N2+2H2OAlloy components exposed to untreated steam corrode significantly faster than identical components in steam treated with hydrazine.
Use the equation and your scientific knowledge to explain how hydrazine reduces the rate of corrosion of these iron-based alloy components.
97 exam-style questions on Edexcel GCSE Chemistry 6.1 Transition metals, alloys and corrosion, covering 6.1.1 Properties of transition metals, 6.1.2 Corrosion and its prevention, and 6.1.3 Alloys and the uses of metals. Each one has a worked solution and a mark scheme showing where the marks go.