Equations for Period 3 Oxides with Acids and Bases

You need to be able to write equations for the Period 3 oxides reacting with simple acids and bases. In every case the products are a salt and water.Basic oxides with acids:Na₂O + 2HCl → 2NaCl + H₂O
MgO + 2HCl → MgCl₂ + H₂O
MgO + H₂SO₄ → MgSO₄ + H₂OAcidic oxides with bases:SiO₂ + 2NaOH → Na₂SiO₃ + H₂O
P₄O₁₀ + 12NaOH → 4Na₃PO₄ + 6H₂O
SO₂ + 2NaOH → Na₂SO₃ + H₂O
SO₃ + 2NaOH → Na₂SO₄ + H₂OSilicon dioxide only reacts with hot, concentrated NaOH, forming sodium silicate. The salts from the sulfur oxides are sodium sulfite (Na₂SO₃) and sodium sulfate (Na₂SO₄). Aluminium oxide reacts with both acids and bases, as shown in the previous lesson.A useful shortcut: an acidic oxide reacts as if it were the acid it forms with water. SO₃ behaves like H₂SO₄, so it needs 2NaOH.Worked example: balance P₄O₁₀ + NaOH → Na₃PO₄ + H₂O. Four P atoms give 4Na₃PO₄, which needs 12 Na, so 12NaOH. The 12 H atoms from 12NaOH make 6H₂O. Check O: 10 + 12 = 22 on the left, 16 + 6 = 22 on the right.