问题 填空题

(6分)下表是某地市场销售的一种“加碘食盐”包装袋上的部分文字说明。

配 料氯化钠、碘酸钾
含碘量(20mg~40mg)/1kg
保质期18个月
食用方法勿长时间炖炒
贮藏指南避热、防潮
(1) 由食用方法和贮藏指南可推测碘酸钾的化学性质之一是_____     __________。

(2) 已知碘在碘酸钾中的化合价为+5,碘酸钾的化学式为__________    _______。

(3)用单质碘(I2)与氯酸钾发生置换反应可制得碘酸钾,该反应的化学方程式为

_____________________________________________________________。

答案

(6分)(1)不稳定,受热易分解  (2)KIO3   (3)I2+2KClO32KIO3+Cl2

题目分析:(1)根据题意可知,加碘盐需要避热、防潮,且在使用时不能长时间炖炒,这说明碘酸钾的化学性质之一是不稳定,受热易分解。

(2)由于化合物中元素化合价的代数和为0,由于K的化合价是+1价,而氧元素的化合价是-2价,所以碘酸钾的化学式是KIO3

(3)用单质碘(I2)与氯酸钾发生置换反应可制得碘酸钾,这说明单质碘是还原剂,被氧化,所以反应的方程式是I2+2KClO32KIO3+Cl2↑。

点评:再利用化合价判断化合物的化学式时,应该紧紧抓住元素化合价的代数和为0这一关系式进行分析。

选择题
阅读理解

I have studied in the boarding school in UK for about two years, and I really like it very much.

I always wanted to run a business of some sort; and finally I got such a good chance to do

so at the beginning of the summer term. The business project is called Young Enterprise, where we set up a small company called “Limitless” and sold the products to the school and public. I was appointed deputy director and financial director of the company, in which my role was to manage the financial activities.

I have learn so much from this experience, for I could put what I has learnt into practice in a real life and learn to work with different people, which improved my skills in management and communication.

In this school we students can organize out own activities if we want to, and the school is usually highly supportive: so this term I have organized an Engineering Society in school, which arranges regular visits to local industries. So far, the society which has only 10 members has proved to be really “popular”. Well, it is always the quality, not the quantity, that matters, isn’t it?

I have had many opportunities to challenge myself since I got to the school, and I do think it is all of these challenges that make me more and more mature. Perhaps one of the most important lessons I have learned in this school is to have the initiative (主动) to look for any possible challenges.

63. Why does the writer like this boarding school so much?

A. Because he has learned there for about two years.

B. Because he ran a business of his own.

C. Because he has many opportunities to look for any possible challenges initiatively.

D. Because he was promoted to be deputy director and financial director of the company.

64. What’s the writer’s duty in the small company called “Limitless”?

A. To be in charge of the finance of the business.

B. To put what he has learned into practice.

C. To work with people from different backgrounds.

D. To find out how the consumers bought their products.

65. He has learnt a lot about _______ from the experience of running a small company.

A. what the teacher don’t know    B. what can’t be learned from books

C. financial knowledge           D. management and communication skills

66. From the passage, we know that ________.

A. the school usually supports the students activities

B. all of the students’ activities are supported by the school.

C. the school usually organize the students’ activities directly

D. the writer is not the organizer of the Engineering Society in the school