在研究酸和碱的化学性质时,某小组同学想证明:稀硫酸与NaOH溶液混合后,虽然仍为

题型:实验题

问题:

在研究酸和碱的化学性质时,某小组同学想证明:稀硫酸与NaOH溶液混合后,虽然仍为无色溶液,但确实发生了化学反应。请与他们一起完成实验方案的设计、实施和评价。

(1)方案一:①测定稀硫酸与NaOH溶液混合前后的pH。测定某NaOH溶液的pH,pH       7(选填“<”“>”或“=”)。

②将一定量的稀硫酸加入该NaOH溶液中,混合均匀后测定其pH,pH<7。

③结论:稀硫酸与NaOH溶液发生了化学反应,并且       过量。

(2)方案二:观察       。(根据图示实验步骤,概括方案要点)

结论:稀硫酸与NaOH溶液发生了化学反应,反应的化学方程式为                             

(3)上述两个方案在设计思想上的相同点是                            

考点:中和反应及在实际中的应用酸的性质碱的性质
题型:实验题

2013年10月由江西省鄱阳湖自然保护区管理局启动开展了“千里迎候鸟”活动。在鄱阳湖候鸟自然保护区,成群的大雁、白鹤、斑嘴鸭、鸿雁等珍禽候鸟栖息于此,有的翩翩起舞,有的自由自在觅食。这体现了(    )

A.生命是可爱的

B.人与自然和谐共处

C.世界因生命而精彩

D.尊重生命,善待大自然

题型:实验题

回收式自身输血输注注意事项正确的是()。

A.术中回收处理的血液不用者可以转让给其他患者使用

B.应予以补充血小板、凝血因子、血浆蛋白等

C.术中回收处理的血液含有的游离血红蛋白无需相应治疗

D.行术中回收式自身输血的患者术后无需常规使用抗生素

E.术中回收处理的血液回输时不必使用输血器

题型:实验题

第二节信息匹配题(共5小题,每题2分共10分)

注意:此答案要写在答题纸上

Making friends is a skill like most skills. It improves with practice. If you want to meet people and make friends, you must be willing to take some action. You must first go where there are people. 56 

Joining a club or a group, talking with those who like the same things as you do is much easier.Or join someone in some activity.

57 After all meeting strangers means facing the unknown. And it's human nature to feel a bit uncomfortable about the unknown. Most of our fears about dealing with new people come from doubts about ourselves. We imagine other people are judging us, finding us too tall or too short, too this or too that. 58   Try to accept yourself as you are, and try to put the other person at ease. You'll both feel more comfortable.

Try to act self-confident even if you don't feel that way. When you enter a room full of strangers, such as a new classroom,walk tall and straight, look directly at other people and smile, and say something. 59 

Just meeting someone new does not mean that you will make friends with that person--friendship is based on mutual (相互的)liking and  "give and take".   60 

A.Don't wait for the other person to start a conversation.

B.But don't forget that they must be feeling the same way.

C.It depends on one's character to make good friends.

D.You won't make friends staying home alone.E.Many people are nervous when talking to new people.

F.It takes time and effort to develop.

G.I'm a shy person and it is very difficult for me to make friends with other people.

题型:实验题

喉部的常规影像学检查技术是()

A.X线

B.CT

C.MRI

D.超声

E.DSA

题型:实验题

下列现象发生于北宋的是()

A.相秉社稷之重,总百僚之任

B.置使以总国计,应四方贡献之入,朝廷之预,一归三司

C.阁臣职参机务,今止票拟,而裁决归近习

D.威命所寄,不于内阁而于军机处,盖隐然执政之府矣

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