某种催化剂为铁的氧化物。化学兴趣小组在实验室对该催化剂中铁元素的价态进行探究:将

题型:实验题

问题:

某种催化剂为铁的氧化物。化学兴趣小组在实验室对该催化剂中铁元素的价态进行探究:将适量稀硝酸加入少许样品中,加热溶解;取少许溶液,滴加KSCN溶液后出现红色。一位同学由此得出该催化剂中铁元素价态为+3的结论。

(1)请指出该结论是否合理并说明理由__________________________________________。

(2)请完成对铁元素价态的探究:

限选实验仪器与试剂:烧杯、试管、玻璃棒、药匙、滴管、酒精灯、试管夹;3 mol./L H2SO4、3% H2O2、6 mol/L HNO3、0.0l mol/L1KMnO4、NaOH 稀溶液、0.1 moI/LKI、20%KSCN、蒸馏水。

①提出合理假设

假设1:_________________________;

假设2:_____________________;

假设3:___________________ 。

②设计实验方案证明你的假设

③实验过程根据②的实验方案,进行实验。请在答题卡上按下表格式写出实验操作步骤、预期现象与结论。

考点:设计实验方案及探究实验铁盐(三价铁离子)亚铁盐(二价铁离子)
题型:实验题

振法可用于 ()

A.胸部

B.腹部

C.头面部

D.全身各部

E.腰背部

题型:实验题

某工厂计划做一批零件,原计划10天完成任务,实际每天平均比原计划多做15个,结果提前3天完成任务.该工厂原计划做零件多少个?

题型:实验题

第二节 根据对话内容,从对话后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。(共5小题,每小题1分,满分5分。注:请将此题答在第Ⅱ卷上)

 61

— Of course. Different jobs need people with different characters.

— Could you give me an example?

— Yeah.  62  However, an extremely independent one isn’t

— Almost right! And I think there is some moral (道德的) conduct all people should have at work.

 63

— Respect, duty, fairness, honesty and so on.

— It seems that they are all important. But it’s really hard to have all of the good moral conduct.

 64   But firstly, you should treat the person whom you work with with kindness and respect. Then you should learn to be brave and careful.

 65

— Yes.

— If so, I’ll have a try.

A.No doubt about it.

B.What is it?

C.Absolutely! We must be dependable.

D.You’d better get along well with everyone.E.Do you think the character plays an important role in one’s career?

F.Then I’ll be rated(评价) as a priceless diamond by my boss?

G.You see, an easy-ging person is suitable for teamwork.

题型:实验题

石墨列管特点是()

A、传热效果好,耐磨、抗腐、低结垢

B、传热效果好,抗腐、有较高的机械强度

C、传热效果好,抗腐、防振、耐磨

题型:实验题

为了保证航行安全,郑和船队的每只船上都要装()个罗盘

A、7

B、5

C、1

D、3

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