下列叙述错误的是[ ] A．带相反电荷离子之间的相互吸引称为

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问题不定项选择题

下列叙述错误的是[ ]

A．带相反电荷离子之间的相互吸引称为离子键

B．金属元素与非金属元素化合时，不一定形成离子键

C．某元素的原子最外层只有一个电子，它跟卤素结合时所形成的化学键不一定是离子键

D．非金属原子间不可能形成离子键

答案

实验题

某化学兴趣小组对一包干燥的红色粉末组成进行探究，请你参与并回答有关问题。

【老师提醒】它由铜、氧化铁两种固体中的一种或两种组成。

一、【提出猜想】红色粉末可能的组成有：

①只有铜；

②只有；

③是铜、氧化铁的混合物

【资料获悉】

①铜在氯化铁溶液中发生反应：2FeCl₃+Cu=2FeCl₂+CuCl₂

②氧化铁能被稀盐酸溶解：Fe₂O₃+6HCl=2FeCl₃+3H₂O

二、【实验探究】

（1）甲同学取少量红色粉末于试管中，滴加足量稀盐酸，震荡后观察，发现固体全部溶解。甲同学认为可以排除猜想中的①和③，而乙同学认为只能排除猜想①，你认为（填“甲”或“乙”）的观点正确。

（2）丙同学为进一步确定红色粉末的组成，称取该粉末5g装入硬质玻璃管中，按下图在同分橱中进行试验。开始时缓缓通入CO气体，过一段时间后再加热使其充分反应。待反应完全后，停止加热，仍继续铜CO气体直至玻璃管冷却。反应前后称量相关装置和物质的总质量，其数据如下表：

三、【讨论交流】

（1）在装置A中先通入CO气体的作用是。

（2）应该选择组的实验数据计算确定红色粉末的组成。最终计算结果表明：该红色粉末的组成是猜想中的第组（填序号）

（3）写出A装置中发生的化学方程式及现象。

（4）为了防止溶液倒吸，本实验停止加热前是否需要先断开A和B的连接？（填“需要”或“不需要”），理由是。

四、【反思评价】丁同学指出：从环保角度，上图装置有严重不足之处。你认为应该如何改进？。

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完形填空

Once upon a time, a man punished his 5-year-old daughter for using up the family's only roll of expensive gold wrapping paper. Money was tight, and he became even more____when on Christmas Eve, he saw____ the child had pasted the gold paper so as to decorate a shoebox to put under the Christmas tree.
______, the next morning the little girl, filled with excitement, brought the gift box to her ____ and said, "This is for you, Daddy!" As he opened the box, the father was _____ by his earlier overreaction.____when he opened it, he found it was____ and again his anger flared. "Don't you know, young lady,” he said harshly, “____ you give someone a ____ there's supposed to be something inside the package!"The little girl looked____ at him with tears rolling from her eyes and said: "Daddy, it's not empty. I blew kisses into it until it was all full." The father was ____. He fell on his knees and put his arms around his precious little girl. He begged her to____ him for his unnecessary anger.
An accident took the____ of the child only a short time later. ____is told that the father kept that little gold box by his bed for all the years of his life. ____ he was discouraged or faced difficult problems he would open the box, take ____ an imaginary kiss, and remember the love of this beautiful child ____ had put it there.
In a very real sense, each of us as human beings have been given an____golden box filled ____ unconditional love and kisses from our children, family, friends and God. There is no more____possession anyone could hold.

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