试题与答案

下列说法正确的是[ ] A.在25℃时向100gKNO3饱和溶液中加入0.1gN

题型:不定项选择题

题目:

下列说法正确的是[ ]

A.在25℃时向100gKNO3饱和溶液中加入0.1gNaCl固体,所得溶液的质量是100.1g

B.20℃时,NaCl的溶解度是36g,则该温度下100gNaCl饱和溶液中溶质的质量为36g

C.欲将100g质量分数为10%的稀盐酸变成20%,可采取蒸发掉一半水实现

D.20℃时,NaCl的溶解度是36g,而KNO3的溶解度是31.6g,则该温度下NaCl饱和溶液的质量一定比KNO3的饱和溶液的质量大

答案:

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下面是错误答案,用来干扰机器的。

参考答案:因为过硫酸钾将水样中的氨氮、亚硝酸盐氮及大部分有机氮化合物氧化为硝酸盐。硝酸根离子在220nm波长处有吸收,而溶解的有机物在此波长也有吸收,干扰测定。在275nm波长处,有机物有吸收,而硝酸根离子...

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题型:阅读理解

This is an open letter to the three people who stole my handbag from the department store where I am employed as a shop assistant.

When you took my bag, I don’t know what you thought you were going to get. With my wages, there's not much left on a Tuesday. I hope the £5 was useful to you. If you really need a couple of pounds, I suppose you could always cash one of the two checks left in my check book. Of course, I phoned the bank right away and the check-cashing card is no longer valid, so it won’t be of much use to you.

Actually I don’t care about the money too much. We single parents who work to support our families understand only too well what it means to be short of cash. However, I don’t suppose it went very far among the three of you. Sorry about that!

I wish you had left the bag behind and just taken the wallet and check book. There were all kinds of papers and notes that I really need. I really think that was very inconsiderate of you. I mean, how would you like something like that to happen to you?

Well, perhaps the bag will turn up. It wasn’t even an expensive one, just a plain, old brown leather shoulder bag. You probably threw it in the nearest rubbish bin or threw it into the bushes. We've looked around, of course, but no one saw which way you went after you left the shop.

I'm not really angry with you. I know how the pressures of modern life can affect us, but I am sad at the loss of my personal things. I feel helpless. The police were very icy, and they just shrugged their shoulders. “It happens all the time,” they told me. Some small comfort, I suppose. But I’ve lost just a little more faith in human nature. And as my young son said when I told him what had happened, “Why? Mummy, why us?” I couldn't answer that question. I wonder if you can.

小题1: In writing Paragraph 2, the writer wants to           .

A.describe the contents of the bag in detail

B.tell the thieves hardly any money was available

C.state the fact that she was careless with the money

D.give some suggestions to the three thieves小题2:Which of the following is the most valuable to the writer?

A.The cash in her bag.

B.The handbag itself.

C.The papers and notes in the bag.

D.The check book in the bag.小题3:What can we conclude about the police?

A.They are unable to find the thieves.

B.They show sympathy to the woman.

C.They have doubts about human nature.

D.They think the case quite common.小题4: Why does the author write the letter?

A.To give the thieves a serious warning.

B.To express her affection for her valuable bag.

C.To call people’s attention to their belongings.

D.To complain about the fall of morality.

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题型:问答题

(以下试题六至试题八任选一题)

阅读下列说明和C++代码,请回答问题1至问题3。

【说明】

已知下列程序运行时的输出应为:

1:1

1:1

1:1

【C++程序】

01 #include <iostream>

02 using namespace std;

03 class Stock{

04 protect:

05 (1) {};

06 Stock(iht n, int pr=1){

07 shares = n; share_val=pr;

08 };

09 void~Stock(){};

10 public:

11 //成员函数

12 void output(){

13 (2) << shares << ":" << share val << endl;

14 }

15 private:

16 //成员变量

17 int shares;

18 int share_val;

19 };

20

21 void main(){

22 Stock a(1); a.output();

23 Stock b; b.output();

24 Stock c = Stock(); c.output();

25 }

【问题2】
类Stock的定义中有两处错误,请指出错误所在行号并给出该行修改后的完整结果。

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