1) Fe + 3NaOH → Fe(OH)₃ + 3Na;
2) 2Fe(OH)₃+3CuSO₄ → Fe₂(SO₄)₃+3Cu(OH)₂↓
3) Fe₂(SO₄)₃(t°) → Fe₂O₃+3SO3↑
4)Fe₂O₃+2Al → 2Fe+Al₂O₃
1) Fe + 3NaOH → Fe(OH)₃ + 3Na;
2) 2Fe(OH)₃+3CuSO₄ → Fe₂(SO₄)₃+3Cu(OH)₂↓
3) Fe₂(SO₄)₃(t°) → Fe₂O₃+3SO3↑
4)Fe₂O₃+2Al → 2Fe+Al₂O₃