某小组在实验室进行关于氧气的实验,所用的部分仪器如下图所示. ①甲同学用双氧水

题型:问答题

问题:

某小组在实验室进行关于氧气的实验,所用的部分仪器如下图所示.

①甲同学用双氧水制取氧气,发生反应的化学方程式是______,选择的收集装置是D或______,用D收集氧气时验满的方法是______(操作、现象、结论).

②乙同学用氯酸钾和二氧化锰为原料制取氧气,二氧化锰的作用是______,应选择的发生装置是______.该同学发现产生的气体能使带火星的木条复燃并有刺激性气味,下列分析不合理的是______.

a反应中氧气的物理性质发生了变化

b此时得到的气体一定是混合物

c只加热氯酸钾,若生成的气体无气味,说明刺激性气味一定与二氧化锰有关

d可能是生成的氧气与残留在发生装置中的空气在加热的条件下反应生成了新物质.

③丙同学研究了木条复燃与氧气体积分数的关系,发现不纯的氧气也能使带火星的木条复燃.如图F是他其中一次实验的装置,排尽水收集氧气后集气瓶中氧气的体积分数是______(列式即可).

考点:氧气的制取和收集
题型:问答题

生后3天的新生儿,查血红蛋白为110g/L,其贫血的程度是

A.轻度

B.中度

C.重度

D.极重度

E.无贫血

题型:问答题

阅读理解。

       There is a park near my home. People like to go to this park after work. Some of them go to the

park every day. Look! This is Mr. King. He is sitting on a chair and watching the children. Some

children are playing a game. Some boys are playing football. Lucy and Lily are standing under a big tree.

They are talking about their favorite movies. There is a small river in the park. We can see some boats

on the water. Some children are sitting in the boats with their parents. Listen! A girl is singing. It's really

a nice park. I come here every day.

1. Who likes to go to the park?

A. Children.   

B. Parents.

C. Lucy and Lily.

D. People.

2.There are some _____ in the park.

A. birds and cats  

B. chairs and boats

C. balls and kites

D. houses and buses

3. Lucy is talking with _____.

A. Mr. King

B. the boys

C. Lily

D. her parents

4. We can't see ______ in the park.

A. children

B. men

C. women

D. bird 

5. What is the writer doing? 

A. He's watching the people in the park.

B. He's playing a game.

C. He's sitting in a boat.  

D. He's singing under the tree.

题型:问答题

A lot of cities, ___ Shanghai and Guangzhou , are getting more and more beautiful.

A.such as

B.such like

C.so as

D.as

题型:问答题

通过湿式过滤器后洁净空气的灰尘含量少于()mg/m3

A.0.05

B.0.5

C.1

D.1.5

题型:问答题

养阴清肺膏善治()

A.风热咳嗽

B.风寒咳嗽

C.肺热咳嗽

D.燥咳无痰

E.痰湿阻肺

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