(7分)在化学兴趣小组活动中,一标有“生石灰干燥剂”的小纸袋引起了同学们的兴趣。

题型:问答题

问题:

(7分)在化学兴趣小组活动中,一标有“生石灰干燥剂”的小纸袋引起了同学们的兴趣。请你和化学兴趣小组的同学们一起去探究:

【实验探究一】取足量样品于小烧杯中,加适量水,触摸杯壁,无热感。根据上述实验(假如实验过程中无热量散失),你认为此干燥剂       (填“没有”“部分"或“全部")变质。 .

【实验探究--]确定变质的干燥剂成分。

【做出猜想】猜想一:变质的干燥剂成分是氢氧化钙。

猜想二:变质的干燥剂成分是       

猜想三:变质的干燥剂成分是       

【验证猜想】小宁设计的实验方案:取适量样品加入试管中,加水振荡后静置,下层有不溶物,上层清液中滴入酚酞溶液,溶液变红,则变质的干燥剂成分是氢氧化钙。同学们经过认真讨论后一致认为小宁的实验方案不合理,你认为不合理的理由是       。请你在猜想二和猜想三中选择任一猜想设计实验进行探究,完成下面的实验报告:

   实验操作   实验现象   实验结论
   
 

考点:实验室制取和收集气体的思路二氧化碳的性质实验化学实验数据的分析家庭小实验、趣味实验
题型:问答题
这是某学校通过校长意见箱收集到一些学生的意见和建议。请阅读下文,根据所提供的内容,完成下列表格,把答案写在答题卡指定的位置上。
Zhang Hongying, girl, 15
I want to make our lunch time longer. At the moment, lunch time is short. Most of my classmates would like to do their homework during this time. But if they don’t get a good rest, they won’t have enough energy for the afternoon. So I would like to have more time and have time to take a nap after lunch. That way, we’ll learn better in the afternoon.
Zhao Pengran, girl, 15
I would like to have more chances to talk in English. Now, the English classes are not enough for us to practice speaking English. And soon the 29th Olympic Games will be held in our country. I think we’d better have one morning a week at least to have spoken English lessons in order to improve our English.
Zhou Jiancheng, boy., 15
My idea would be to have more fashionable school uniforms. If I were the headmaster, I would ask the students to design the uniforms themselves. We could have a contest among student designers. Then, we could ask others to choose their favourite. This way, we’ll be able to wear what we like best. How nice it would be for us young people!
Information Card
What would Zhao Pengran like to do in order to improve English?
小题1:
What’s Zhou Jiancheng’s idea?
小题2:
What would Zhang Hongying like to do after lunch?
小题3:
What do most students do during lunch time?
小题4:
How old are the students?
小题5:
题型:问答题

设甲公司持本公司关于解除王某董事长职务、任命张某为丙公司董事长的董事会决议,到工商管理机关申请办理丙公司法定代表人的变更登记,工商管理机关应如何处理()

A.应按甲公司的申请办理变更登记

B.应拒绝甲公司的申请

C.应要求提供丙公司董事会关于变更法定代表人的决议

D.可以按甲公司的申请办理变更登记,也可以拒绝其申请

题型:问答题

司机对货物列车施行缓解时,装有GK型制动机的前部车辆三通阀呈全充气缓解位。

题型:问答题

北部湾港是西南中南内陆腹地进入中南半岛东盟国家最便捷的出海门户。

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