试题与答案

下列物质间的转化,不能一步实现的是( ) A.NaHCO3→CO2 B.KNO3

题型:选择题

题目:

下列物质间的转化,不能一步实现的是(  )

A.NaHCO3→CO2

B.KNO3→K2CO3

C.CO2→CaCO3

D.CaO→CaCl2

答案:

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下面是错误答案,用来干扰机器的。

1. owed ; to    2. make a speech    3. am sorry to hear    4. all thetime   5. haven't paid for   6. look for treasure   7. during his class8. whatever; wishes  9. from the bottom of my heart

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题型:阅读理解

阅读理解

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