One day a dentist was starting his morning work. Suddenly a man ran in. His face was red and he could only say “Quick! Quick!”, The dentist thought he must be very ill. His assistant(助手) helped to make the poor man sit in a chair. The dentist gave the man some medicine to make him sleep. Then, he looked into the man’s mouth and pulled out all the bad teeth. As soon as the man woke up(醒来), he said in a low voice, “Quick, doctor, quick.”

“It’s all right now,” the dentist told him, “It’s over.”

“You don’t understand,” said the man, “I came to tell you your house is on fire.”

根据短文内容，选择正确答案。

小题1:The story happened        .

A．in the morning

B．in the afternoon

C．in the evening

D．at night小题2:When the man ran in, the dentist thought he must be         .

A．over

B．ill

C．all right

D．rich小题3:The man          after he took some medicine.

A．began to work

B．began to cry

C．went home

D．went to sleep小题4:The dentist pulled          out of the man’s mouth.

A．a tooth

B．a bad tooth

C．all the bad teeth

D．all the teeth小题5:The man ran in          .

A．bacause he was ill

B．because he wanted to sleep

C．to tell the dentist that he was all right

D．to tell the dentist that his house was on fire

（7分）做钠在氯所中燃烧的实验时，钠完全反应后，在集气瓶内放少量水来吸收过量的Cl₂，但不能完全吸收。如何处理残余的Cl₂呢？同学们进行了相关探究。

【提出问题】

向上述集气瓶中滴入石蕊溶液，发现溶液显红色。由此想到，选用氢氧化钠等碱性溶液吸收Cl₂，效果会怎么样？

【查阅资料】

氯气是黄绿色有毒气体，溶于水，在饱和氯化钠溶液中的溶解度非常小。

【设计与实验】

用两套完全相同的装置做对比实验，如下图所示：

（1）为确保实验的准确性，要先检验装置的_____________________；

（2）实验开始时，先用弹簧夹夹紧乳胶管，再将注射器内等体积的水和NaOH溶液分别注入充满Cl₂的集气瓶；

（3）充分吸收Cl₂后，打开弹簧夹，观察进入两个集气瓶内饱和NaCl溶液的体积。

【结论与解释】

（1）甲实验中，Cl₂溶于水且与水反应生成盐酸和次氯酸（HClO），反应的化学方程式为____________________________________。

（2）乙实验中，Cl₂与NaOH易发生化学反应。

（3）分析实验现象得知，用碱性溶液比用水吸收Cl₂的效果_________（填“好”或“差”）

【交流与反思】

（1）金属钠在氯气中燃烧的实验现象为__________________________________。

（2）向Cl₂的水溶液中滴入硝酸银溶液有白色沉淀生成，化学方程式为：

_____________________________________________。