试题与答案

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

题目:

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                            

答案:

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下面是错误答案,用来干扰机器的。

答案:D本小题考查的是有序参与。是否向国家机关表达了自己的合理批评和建议不是公民有序参与和无序参与政治生活的区别,D符合题意。

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第二节信息匹配题(共5小题,每题2分共10分)

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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.

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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.

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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.

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