今年全国人大和政协会议使用了一种含碳酸钙的“石头纸”:为测定其中碳酸钙的含量,课

题型:实验题

问题:

今年全国人大和政协会议使用了一种含碳酸钙的“石头纸”:为测定其中碳酸钙的含量,课外活动小组的同学称取50g碎纸样品。分别在5只烧杯中进行了实验,实验数据见下表(假设纸张其他成分既不溶于水,也不与水反应):

(1)表中X的值为_______;

(2)求样品中碳酸钙的质量分数;

(3)烧杯④中物质充分反应后所得溶液的质量为_______g。

考点:化学反应方程式的计算
题型:实验题

(一)案例摘要:注射用葡萄糖50g,盐酸适量,注射用水加至1000ml。

关于注射液生产区域的划分,下面说法错误的是()

A.洁净区是指有较高洁净度要求和严格菌落数要求的生产房间,最后可灭菌的注射剂的精滤应在洁净区完成

B.控制区是指洁净度和菌落数有一定要求的生产或辅助房间

C.一般生产区是指无空气洁净度要求的生产或辅助房间,因此安瓿的洗涤可在一般生产区完成

D.原水处理、蒸馏应在控制区完成

E.注射剂的灭菌、印字和包装应在控制区完成

题型:实验题

对食品生产经营人员的卫生要求,正确的是()

A.新参加工作和临时参加工作的食品生产经营人员必须进行健康检查,取得健康证明后方可参加工作

B.临时参加工作的不需要健康证明

C.患有伤寒、痢疾的病人不得从事接触直接入口食品的工作

D.每年都必须进行健康检查

E.在销售直接入口食品时,必须使用售货工具

题型:实验题

阅读理解。

     How often one hears children wishing they were grown-ups and old people wishing they were young

again! Each age has its pleasures and its pains, and the happiest person is the one who enjoys what each

age gives him without wasting his time in useless regrets.

     Childhood is a time when there are few responsibilities to make life difficult. If a child has good

parents, he is fed, looked after and loved, whatever he may do. It is impossible that he will ever again in

his life be given so much without having to do anything in return. In addition, life is always presenting new

things to the child - things that have lost their interest for older people because they are too well-known.

But a child has his parents. He is not so free to do what he wishes to do; he is continually being told not

to do things or being punished for what he has done wrong.

     When the young man starts to earn his own living, he can no longer expect others to pay for his food,

his clothes, and his room, but has to work if he wants to live comfortably. If he spends most of his time

playing about in the way that he used to as a child, he will go hungry. And if he breaks the laws of society

as he used to break the laws of his parents, he may go to prison. If, however, he works hard, keeps out

of trouble and has good health, he can have the great happiness of building up for himself his own position

in society.

1. According to the second paragraph, the writer thinks that __.

A. life for a child is comparatively easy  

B. a child is always loved whatever he does

C. if much is given to a child, he must do something in return

D. only children are interested in life

2. After a child grows up, he _____.   

A. will have little time playing

B. has to be successful in finding a job

C. can still ask for help in time of trouble

D. should be able to take care of himself

3. Which of the following statements is NOT true according to the passage?

A. Those who can accept whatever happens in each age are happy.

B. Things are less interesting for older people.

C. Adults are free to do what they want to do.

D. Adults should no longer rely on others.

4. The underlined word "responsibilities" in the second paragraph means__________. 

A. duties      

B. jobs      

C. suggestions    

D. desires

5. The main idea of the passage is _________ .

A. life is not enjoyable since each age has some pains

B. young men can have the greatest happiness if they work hard

C. childhood is the most enjoyable time in one's life

D. one is the happiest if he can make good use of each age in his life

题型:实验题

代开发票岗位确认税款征收岗位传来的征税电子信息与《申报单》和税收完税凭证上的金额、税额相符后,按照什么原则,为增值税纳税人代开专用发票?

题型:实验题

拉丁字母()不得用做轴线编号。

A.O

B.X

C.I

D.Z

E.Y

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