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问题 填空题

如图所示，给试管中的水加热到沸腾，水蒸气把软木塞冲开，说明水蒸气膨胀时对软木塞______，消耗了水蒸气的______能，转化为软木塞的______能．

答案

给试管中的水加热到沸腾，水蒸气把软木塞冲开，水蒸气膨胀时对软木塞做功，水蒸气的内转化为木塞的机械能，水蒸气的内能减少，木塞的机械能增加．

故答案为：做功；内；机械．

阅读理解

阅读理解。

1. The number of the students who took part in English competitions in ______ grew faster

   from 2008 to 2009. [ ]

A. School A

B. School B

C. neither school

2. In the English competition in ______, School B had 100 more students than School A. [ ]

A. 2007

B. 2008

C. 2009

3. According to the information above,these two schools had the sanle percentage of the

   students who won prizes in ______.[ ]

A. 1istening

B. speaking

C. reading

4. ______ students in School A were given prizes for their speaking skill in 2009. [ ]

A. 100

B. 200

C. 300

5. Which of the following is TRUE from the information above? [ ]

A. The students from School A and School B won prizes in five skills.

B. The students from School B did wont in listening of all skills.

C. The students from School A need to improve their writing skills.

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实验题

某学生利用下图装置进行实验来鉴别Na2CO3和 NaHCO3。

(1)该装置图有三处错误，试指出错误并改正_____________。

(2)证明固体中存在NaHCO3的实验现象是什么？_____________

(3)实验后如何撤除装置？____________

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