Осуществите цепочки превращений S⇒S02⇒H2SO3⇒Na2SO3 Ca⇒CaO⇒Ca(OH)2⇒Cacl2
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S + O₂ = SO₂
SO₂ + H₂O ⇄ H₂SO₃
H₂SO₃ + 2NaOH = Na₂SO₃ + 2H₂O
2Ca + O₂ = 2CaO
CaO + H₂O = Ca(OH)₂
Ca(OH)₂ + 2HCl = CaCl₂ + 2H₂O