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Question
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
Solution
Manganese is extracted from its oxide (Manganese dioxide or MnO2 ) by using aluminium as the reducing agent. Because aluminium is more reactive than manganese and is placed above it in the reactivity series, aluminium can easily displace manganese from its oxide to liberate the metal.
Manganese dioxide is heated with aluminium powder to produce manganese.
3MnO2(s) + 4Al(s) → 3Mn (l) + 2Al2O3(s) + Heat
The reaction is highly exothermic and huge amount of heat is liberated. Thus, manganese will be produced in molten (liquid) state.
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