将200mL稀硝酸与6.4g的铜粉在微热的条件下充分反应,还原产物为NO,经测定

题型:问答题

问题:

将200mL稀硝酸与6.4g的铜粉在微热的条件下充分反应,还原产物为NO,经测定NO的体积为1.12L(标准状况).

(1)写出铜与稀硝酸反应的离子方程式:______

(2)求出该硝酸溶液中HNO3的物质的量浓度及参加反应的铜的质量;

(3)现用12.5mol•L-1的浓硝酸来配制500mL该稀硝酸.可供选择的仪器有:

①玻璃棒②烧瓶③烧杯④胶头滴管⑤量筒⑥托盘天平⑦药匙.上述仪器中,配制时不需要使用的仪器有______(填代号),还缺少的一种仪器是______.

考点:(浓、稀)硝酸
题型:问答题

A

The weather is getting hotter. You are thirsty playing basketball or riding home from school. A cold drink may be just the thing. But be careful what you are drinking. Something that looks cool may not be good for your health.

There are plenty of "energy drinks" on the market. Most of them have beautiful colors and cool names. The lists on them tell you they are helpful to your health. Sounds great!  

But after a careful check you may find that most energy drinks have lots of caffeine (咖啡因) in them. These drinks are especially aimed at young people, students, busy people and sports players. Makers sometimes say their drinks make you better at sports and can keep you awake. But be careful not to drink too much.

Caffeine makes your heart beat fast. Because of this, the International Olympic Committee has limited( 限制) its use. Caffeine in most energy drinks is at least as strong as that in a cup of coffee or tea. Possible health dangers have something to do with energy drinks. Just one box of energy drink can make you nervous, have difficulty sleeping and can even cause heart problems. Scientists say that teenagers should be discouraged from taking drinks with a lot of caffeine in them.

小题1:Many people like drinking energy drinks because of the following EXCEPT that ________.

A.they have beautiful colors and cool names

B.they have lots of caffeine

C.they can keep them awake and better at sports

D.they are said to be helpful to health小题2:The main reason for people not to drink too much energy drinks is that they may cause _____.

A.heart problems

B.nervousness

C.sleeping difficulty

D.possible health dangers小题3:The underlined word "discouraged" can be replaced(替换) with "________".

A.encouraged

B.stopped

C.helped

D.disliked小题4:From the passage we can know that _________.

A.advertisements are important in getting people to buy energy drinks

B.energy drinks are helpful to teenagers' study

C.sports players need to drink a lot of energy drinks

D.energy drinks are especially aimed at teenagers小题5:Which of the following can be the best title(标题) of the passage?

A.What's the Use of Energy Drinks?

B.Who Can Drink Energy Drinks

C.What's That in Energy Drinks?

D.Why Can't We Buy Energy Drinks?

题型:问答题

可移动文物可以分为()。

A.珍贵文物

B.一般文物

C.一级文物

D.二级文物

E.三级文物

题型:问答题

应在绝缘子金属法兰与瓷件的胶装部位涂以性能良好的防水密封胶。()

题型:问答题

职务作品:是指公民为完成法人或其他组织工作任务所创作的作品。

根据以上定义,下列选项属于职务作品的是()。

A.某计算机研究所的清洁工出于爱好开发的一套人事管理软件

B.某市政府干部为省报撰写的《绝对权利观后感》

C.某教师总结多年教学经验撰写的《语文学习妙法》

D.某大学宣传部工作人员接受校方指派拍摄一组校园风景照片

题型:问答题

在考生文件夹下有一个数据库文件“samp3.accdb”,里面已经设计了表对象“tEmp”、窗体对象“fEmp”、宏对象“mEmp”和报表对象“rEmp”。同时,给出窗体对象“fEmp”的“加载”事件和“预览”及“打印”两个命令按钮的单击事件代码,请按以下功能要求补充设计。

已知窗体“fEmp”上的3个命令按钮中,按钮“bt1”和“bt3”的大小一致、且左对齐。现要求在不更改“bt1”和“bt3”大小位置的基础上,调整按钮“bt2”的大小和位置,使其大小与“bt1”和“bt3”相同,水平方向左对齐“bt1”和“bt3”,竖直方向在“bt1”和“bt3”之间的位置。

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