搜题请搜索小程序“爱下问搜题”
问题 填空题

白磷在空气中燃烧的化学方程式______．

答案

白磷在空气中燃烧时，磷与氧气反应生成五氧化二磷．

该反应的化学方程式为：4P+5O2

 点燃 
.
 
2P2O5．

故答案为：4P+5O2

 点燃 
.
 
2P2O5．

问答题

选考题[化学--选修化学与生活]

Ⅰ．维生素C的结构简式是

，它的分子式是______．由于它能防治坏血病，又称为______．在维生素C溶液中滴入紫色石蕊试液，溶液颜色变红，说明维生素C溶液具有______性；在维生素C溶液中滴入少量蓝色的含有淀粉的碘水，可观察到的现象是______，说明维生素C具有______性．

Ⅱ．（1）如右图所示，铁处于Ⅰ、Ⅱ、Ⅲ三种不同的环境中，铁被腐蚀的速率由大到小的顺序是（填序号）______．

（2）氟氯代烷是一种能破坏臭氧层的物质．在大气平流层中，氟氯代烷受紫外线的照射分解出氯原子，氯原子参与下列有关反应：①Cl+O3→ClO+O2  ②O3→O+O2  ③ClO+O→Cl+O2上列的反应的总反应式是______，少量氟氯代烷能破坏大量臭氧的原因是______．
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阅读理解

小题1:Justin Young is a _______.

A．TV reporter

B．popular singer

C．song writer

D．radio reporter小题2: Which song does NOT change its place this week?

A．Are You There?

B．The Bees.

C．Say Cheese.

D．Perhaps.小题3: How many songs listed above are new this week?

A．One.

B．Two.

C．Three.

D．Four.小题4:Which of the following is NOT true according to the passage?

A．You can listen to Music Ground once a week.

B．Justin Young is talking about popular songs this week.

C．People can call in to listen to their favorite songs.

D．Stupid Machine is now in the radio station with OK Band.
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