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问题 选择题

已知在pH为4～5的环境中，Cu2+、Fe2+几乎不水解，而Fe3+几乎完全水解。工业上制CuCl2是将浓盐酸用蒸气加热到80℃左右，再慢慢加入粗氧化铜（含少量杂质FeO），充分搅拌使之溶解。欲除去溶液中的杂质离子，下述方法中可行的是

A．向溶液中通入H2S使Fe2+沉淀

B．向溶液中通入Cl2，再通入NH3，调节pH值为4～5

C．加入纯Cu将Fe2+还原为Fe

D．向溶液中通入Cl2，再加入纯净的CuO粉末调节pH值为4～5

答案

答案：D

填空题

根据上下文及首字母提示完成短文。（每空一词）

      Eric is a good boy. He is 15 1. y____________ old. He is a student in No. 50 Middle School. He has

2. m____________ friends. He likes going to 3. m____________. He likes 4. w____________ TV, too.

He often 5. w____________ football games on TV. His 6. f____________ football star is Beckham. He

wants to 7. b____________ a football player. He thinks playing football is very 8. e____________. Eric

9. h____________ a sister Kathy. She 10. d____________ like football. She likes painting very much.
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问答题

铁丝在氧气中燃烧，生成的黑色固体质量大于参加反应的铁丝质量，用质量守恒定律的知识解释原因．
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