如图是实验室常见的制取气体的装置: (1)写出仪器名称:①______,②__

题型:问答题

问题:

如图是实验室常见的制取气体的装置:

(1)写出仪器名称:①______,②______,③______,④______.

(2)实验室采用装置A制取氧气时,其试管中应放的药品是______,试管口还要放一团棉花,目的是______.

(3)采用装置B制取氧气时,其试管中应放的药品是______,所发生反应的化学方程式是______.

(4)收集氧气可以选择装置______或______,原因是______、______.

(5)某同学收集完毕,先停止加热再将导管移出水面,你预测这种操作会引起什么后果______.

(6)以下是实验步骤,将步骤的序号按正确的先后次序排列为______.

A、点燃酒精灯加热    B、检查气密性              C、熄灭酒精灯      D、向试管中装入药品 

E、收集气体          F、将试管固定在铁架台上    G、从水中撤离导管.

考点:实验室制取和收集气体的思路氧气的制取和收集化学反应方程式的书写文字表达式
题型:问答题

阅读短文,回答问题。

      Mary is an eight-year-old girl. Every day she washes clothes, looks after her younger sister and

works hard on the farm. Mary wants to go to school, but her mother needs her help at home. So Mary

stays at home instead of going to school.

      Do you want to help Mary? Well, join Save the Children, please! Just 6 yuan a day, you can help a

child like Mary. With your help, children like Mary will be able to have enough food and have chances

to go to school.

     Save the Children is an organization to help poor children like Mary. It has been in service since 1932.

The money from kind people will be used to build schools, hospitals and other necessary buildings.

     If you are a volunteer, there are many wonderful things waiting for you -letters from the children,

their photos and subject reports. Now, if you are interested in the application form, and then you can

donate some money. In this way, you can help a child like Mary!

1. What does Mary do every day?

__________________________________________________________

2. How much money does a person need to donate a week

    if he wants to support a child like Mary?

__________________________________________________________

3. What is "Save the Children"?

__________________________________________________________

4. When did Save the Children begin to work?

__________________________________________________________

5. Why doesn't Mary go to school?

__________________________________________________________

题型:问答题

定数等分和定距分中都可以插入块。()

题型:问答题

可调节手铰刀主要用来铰削()的孔。

A.非标准

B.标准系列

C.英制系列

D.德国标准

题型:问答题

避雷器资料及文件验中,下列属于要验收的记录的是()。

A.安装检查及安装过程记录

B.安装过程中设备缺陷通知单

C.设备缺陷处理记录

D.关键点见证记录

题型:问答题

综采工作面供电系统中不包括工作面的通讯、信号控制系统。()

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