Substances are given whose formulas are: NaOH, SO₃, H₂O, CuCl₂. Make equations of possible reactions between them.

2NaOH + SO₃ = Na₂SO₄ + H₂O
SO₃ + H₂O = H₂SO₄; 2NaOH + CuCl₂ = 2NaCl + Cu (OH) ₂

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