下列离子方程式书写正确的是 A．向CaCl2溶液中通入少量CO2气

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问题选择题

下列离子方程式书写正确的是

A．向CaCl₂溶液中通入少量CO₂气体： Ca²⁺+CO₂+H₂O＝CaCO₃↓+2H⁺

B．碳酸钠溶液与硫酸氢钠溶液反应： HCO₃^－+H⁺＝CO₂↑+H₂O

C．向Ba(OH)₂溶液中滴加NH₄HSO₄溶液至刚好沉淀完全：

Ba²⁺+2OH^－+NH₄⁺+H⁺+SO₄²^－＝BaSO₄↓+NH₃·H₂O+ H₂O

D．含有FeBr₂溶液中通入足量的Cl₂： 2Fe²⁺＋4Br^-＋3Cl₂＝2Fe³⁺＋2Br₂＋6Cl^-

答案

A不正确，因为该反应是不能发生的。B不正确，因为反应物是碳酸钠，而不是碳酸氢钠。CD都是正确的，答案选CD。

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完形填空。
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