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问题 单项选择题

一、根据下表回答下面问题。

外资占部分制造业增加值比值的变动情况表

2003年外资占制造业的比重从大到小的正确排列顺序为（）。
①金属制造业②通用设备制造业
③交通运输设备制造业④通信设备计算机及其他电子设备制造业
⑤食品仪表及文化、办公用品机械制造业

A．②①④③⑤

B．①②③⑤④

C．④⑤③①②

D．④③⑤①②

答案

参考答案：C

阅读理解

阅读理解。

A: Hello, Judy. How are you getting along with your word processing (文字处理) class?

B: Well, so far progress has been rather slow. I haven't learned the keyboard yet, and I have problems

    remembering all the orders of editing. I get really impatient because I want to master the means to

    operate the computer as soon as possible.

A: Just remember that Rome wasn't built in a day. Word processing (文字处理) can't be such an easy

    matter.

B: You're right. Our teacher keeps telling us that it takes time to learn all the techniques (技巧) of word 

    processing and that we can't master everything in one day.

A: That' s entirely true. But you'll catch on. Just be patient and practise whenever you can.

1. This dialogue suggests that Judy and the partner ______.

A. may be friends

B. are studying in the same class

C. are both learning word processing

D. are both tired of study

2. What's the main idea of the dialogue?

A. Word processing isn't an easy thing at all.

B.Only step by step can we master something.

C. True friendship will benefit our progress.

D. Truth comes from practice.

3. "Rome wasn't built in a day" means that we should be ______.

A. patient

B. hardworking

C. friendly

D. impatient

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问答题

绿矾（FeSO4•7H2O）是重要的化学化工试剂，工业上常利用机械加工行业产生的废铁屑为原料制备．请回答下列问题：

（1）右图锥形瓶中的反应物是铁屑和28%的硫酸，反应前常用98%的硫酸配制500g 28%的硫酸，要算出所需98%的硫酸的体积，还要知道的数据是______．

（2）在制备硫酸亚铁的过程中，理论上控制铁过量或酸过量均有利于防止Fe2+被氧化．设计两个实验：实验一，控制酸过量；实验二，控制铁过量；其余步骤同，制得硫酸亚铁，并对产品质量进行检测．检测结果如下：

序号反应物用量产品质量
1n（H2SO4）：n（Fe）＞1：1介于Ⅰ级～Ⅱ级之间
2n（H2SO4）：n（Fe）＜1：1优于Ⅰ级
已知产品质量标准：Fe3+的质量分数等于0.005%，产品质量定为Ⅰ级；Fe3+的质量分数等于0.01%，产品质量定为Ⅱ级，从实验结果中，可得出制备硫酸亚铁溶液时，反应控制______过量为最佳．

（3）该小组在继续研究由绿矾制备Fe（OH）2的过程中，发现出现白色的沉淀会逐渐转变为灰绿色，最后变为红褐色．甲同学查资料该灰绿色沉淀可能是Fe3（OH）8，请用氧化物的形式写出该沉淀______；乙同学查资料后认为该灰绿色沉淀是由于Fe（OH）2部分被氧化，混入少量的Fe（OH）3的缘故，请提出一种在研究由Fe2+制备Fe（OH）2的过程中，有助于对沉淀由“白”变“绿”的现象进行合理解释的实验设计新思路______．
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