а) Na → NaOH → Na₂CO₃ → NaCl → NaNO₃. 2Na + 2H₂O = 2NaOH + H₂↑. 2NaOH + H₂CO₃ = Na₂CO₃ + 2H₂O. Na₂CO₃ + 2HCl = 2NaCl + CO₂↑ + H₂O. NaCl + HNO₃ = NaNO₃ + HCl.б) Ca → Ca(OH)₂ → CaCO₃ → CaO → CaCl₂. Ca + 2H₂O = Ca(OH)₂↓ + H₂↑. Ca(OH)₂ + H₂CO₃ = CaCO₃↓ + 2H₂O. CaCO₃ t° → CaO + CO₂↑. CaO + 2HCl = CaCl₂ + H₂O.в) Al → AlCl₃ → Al(OH)₃ → Al₂O₃ → Al₂(SO₄)₃. 2Al + 6HCl = 2AlCl₃ + 3H₂↑. AlCl₃ + 3KOH = 3KCl + Al(OH)₃↓. 2Al(OH)₃ t° → Al₂O₃ + 3H₂O. Al₂O₃ + 3H₂SO₄ = Al₂(SO₄)₃ + 3H₂O.г) C → CO₂ → Na₂CO₃ → CaCO₃ → Ca(NO₃)₂. C + O₂ = CO₂↑. CO₂ + 2NaOH = Na₂CO₃ + H₂O. Na₂CO₃ + CaCl₂ = 2NaCl + CaCO₃↓. CaCO₃ + 2HNO₃ = Ca(NO₃)₂ + CO₂↑ + H₂O.д) P → P₂O₅ → H₃PO₄ → Na₃PO₄ → Ca₃(PO₄)₂. 4P + 5O₂ = 2P₂O₅. P₂O₅ + 3H₂O = 2H₃PO₄. H₃PO₄ + 3NaCl = Na₃PO₄ + 3HCl. 2Na₃PO₄ + 3Ca(NO₃)₂ = 6NaNO₃ + Ca₃(PO₄)₂↓.е) S → SO₂ → Na₂SO₃ → H₂SO₃ → SO₂. S + O₂ = SO₂. SO₂ + 2NaOH = Na₂SO₃ + H₂O. Na₂SO₃ + 2H₂O = 2NaОН + H₂SO₃. H₂SO₃ → SO₂↑ + H₂O.ж) Fe → FeCl₂ → Fe(OH)₂ → FeSO₄ → BaSO₄. Fe + 2HCl = FeCl₂ + H₂↑. FeCl₂ + 2KOH = Fe(OH)₂↓ + 2KCl. Fe(OH)₂ + H₂SO₄ = FeSO₄ + 2H₂O. FeSO₄ + Ba(NO₃)₂ = Fe(NO₃)₂ + BaSO₄↓.з) Fe → FeCl₃ → Fe(OH)₃ → Fe₂O₃ → Fe₂(SO₄)₃. 2Fe + 3Cl₂ = 2FeCl₃. FeCl₃ + 3NaOH = Fe(OH)₃↓ + 3NaCl. 2Fe(OH)₃ t° → Fe₂O₃ + 3H₂O. Fe₂O₃ + 3H₂SO₄ = Fe₂(SO₄)₃ + 3H₂O.