H3PO4 + BaO = NaOH + CuCl2 = Cu(OH)2 + NaCl = HCI + SO3 = NaOH + HF = HCI + Zn = HI + Cu = KOH + SO3 = H2SO4 + BaCl2 = NaOH + CaO = HCI + KNO3 = ZnCI2 + Mg =

Here are the balanced chemical equations for the reactions you listed:

1. H₃PO₄ + BaO → BaHPO₄ + H₂O

2. NaOH + CuCl₂ → NaCl + Cu(OH)₂

3. Cu(OH)₂ + NaCl → No significant reaction under normal conditions (they don't typically react directly)

4. HCl + SO₃ → H₂SO₄

5. NaOH + HF → NaF + H₂O

6. HCl + Zn → ZnCl₂ + H₂

7. HI + Cu → CuI + H₂

8. KOH + SO₃ → K₂SO₄ + H₂O

9. H₂SO₄ + BaCl₂ → BaSO₄↓ + 2HCl

10. NaOH + CaO → Ca(OH)₂

11. HCl + KNO₃ → No direct reaction under normal conditions

12. ZnCl₂ + Mg → No direct simple reaction; they may exchange ions in solution but typically do not react directly as solids

Note: Some reactions depend on conditions; for example, reactions involving gases or solutions may vary.