Na + NaOH -> Na2O + H2Na2O + H2SO4 -> Na2SO4 + H2ONa2SO4 + 2 NaCl -> Na2SO4 + 2 NaClNa2SO4 + 2HCl -> 2NaCl + H2SO42NaCl + 2NaOH -> 2Na2O + 2HClCu + 2NaOH -> Cu(OH)2 + 2Na

Итоговая цепочка реакций: Na -> NaOH -> Na2SO4 -> NaCl -> NaOH -> Cu(OH)2