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问题 单项选择题 A1/A2型题

多发性硬化病理包括（）

A.大脑灰质最常受侵犯

B.多见于额颓叶

C.中枢神经系统内播散的脱髓鞘斑块

D.是一种中枢神经系统白质脱髓鞘性疾病

E.可能与感染人疱疹病毒或逆转录病毒有关

答案

参考答案：C

填空题

原高中教材中有这样一个实验：在两支试管中分别加入3mL稀盐酸，将两个各装有0.3g NaHCO3或 Na2CO3粉末的小气球分别套在两支试管口，将气球内的NaHCO3或Na2CO3同时倒入试管中，观察到现象如下：

（1）两支试管均产生大量气体，投入______的试管中气体产生较快，投入______的试管中气球变得更大（以上均填化学式）．

（2）甲同学用手触摸试管，发现盛NaHCO3粉末的试管变冷，而盛Na2CO3的试管温度有升高．由此他得出：不管其状态如何，NaHCO3和HCl反应为吸热反应，而Na2CO3和HCl反应为放热反应．甲同学写出了下列热化学方程式（其中“aq”的含义是表示水溶液）：HCO3-（aq）+H+（aq）=H2O（l）+CO2（g）△H＞0      CO32-（aq）+2H+（aq）=H2O（l）+CO2（g）△H＜0

甲下结论的方法是否正确______（填“正确”或“不正确”）；为研究是吸热还是放热反应，乙同学继续进行了下列实验（每次实验各做3次平行实验，取平均值）：

序号试剂1试剂2混合前温度混合后最高

或最低温度

①35mL水2.5g NaHCO3固体20℃18.5℃
②35mL水3.2Na2CO3固体20℃24.3℃
③35mL稀盐酸含2.5g NaHCO3的饱和溶液32.5mL20℃19℃
④35mL稀盐酸含3.2g Na2CO3的饱和溶液23.1mL+10ml水20℃24.2℃
⑤35mL稀盐酸2.5gNaHCO3固体20℃16.2℃
⑥35mL稀盐酸3.2g Na2CO3固体20℃25.1℃
请你帮助填写相关内容：

该研究报告的题目可拟为《______》

通过上述实验可得出四条结论：

①NaHCO3的溶解是______ （填“吸热”或“放热”）过程；

②Na2CO3的溶解是______ （填“吸热”或“放热”）过程；

③NaHCO3的饱和溶液和盐酸的反应是______（填“吸热”或“放热”）反应；

④Na2CO3的饱和溶液和盐酸的反应是______（填“吸热”或“放热”）反应．
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阅读理解

(D)

You can not see any object unless light from that object gets into your eyes. Some of the things you see give off light of their own. The sun, the stars, a lighted lamp are examples that can be seen by their own light. Such things are luminous. Most of the things you see are not giving off light of their own. They are simply reflecting light that falls on them from the sun or some other luminous bodies. The moon, for example, does not give off any light of its own. It is non-luminous. You see it because sunlight falls on it and some of it reflects in our direction. So moon light is only second hand sunlight.

When you look at a book, it sends to your eyes some of the light which falls on it, and you see the book. If light could be kept out from where you are so that there would be no light for the book to reflect, then you could not see the book even with your eyes wide open.

Light travels so fast that the time in which it travels from the book you are reading to your eyes is so short as if there were no time at all. Light reaches us from the moon, which is about 380 000 kilometers away, in only a little more than a second.

小题1:You can see the book because_______.

A．your eyes are close to it

B．it reflects some of the sunlight

C．it has light of its own

D．your eyesight can get to it小题2:The underlined word “luminous” means_______.

A．visible

B．all colors

C．giving off light

D．sunlight小题3:________ have light of their own.

A．The sun and the moon

B．The stars and the earth

C．The sun and the stars

D．The moon and the earth小题4:Which of the following is true?

A．All the things you can see give off light.

B．Light from the book is much shorter than that from the moon.

C．The moment you open your eyes the light from the book travels to your eyes.

D．Light travels so fast that there is no time for you to read.小题5:This article is probably from _________ .

A．a science magazine

B．a medical magazine

C．a biography

D．a story book.
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