下图是对四个实验绘制的图像,其中实验结果与图像正确的是( ) A.某温度下,向

题型:选择题

问题:

下图是对四个实验绘制的图像,其中实验结果与图像正确的是(  )

A.某温度下,向一定量接近饱和的硝酸钾溶液中不断加入硝酸钾晶体

B.将稀硫酸滴入一定量的BaCl2溶液中

C.将一定质量的氯酸钾和二氧化锰加入试管中充分加热

D.向pH为13的NaOH溶液中加水稀释

考点:氧气的制取和收集氧气的检验和验满
题型:选择题

(2014届北京市海淀区第一学期期末)根据下图回答问题。

(1)仪器a的名称是              

(2)实验室用大理石和稀盐酸制取二氧化碳的化学方程式为           ,应选用的装置是          (填序号),收集一瓶二氧化碳时,将燃着的木条放在瓶口,若观察到           ,说明瓶中已充满二氧化碳。

(3)取一朵用石蕊溶液染成紫色的干燥小花,将小花的一半用水喷湿,放入装置C中,可观察到的实验现象是             ,此现象说明CO2具有的化学性质是          

(4)小明在查阅资料时发现镁条能在CO2中燃烧,他在装置D中进行实验,发现镁条剧烈燃烧,发出白光,放热,产生一种白色固体和一种黑色固体。这个实验使你对物质燃烧的条件产生的新认识是              

题型:选择题

魏晋时男子服装以长衫为尚,衫与袍的区别在于()

A.袍短而衫长

B.袍有袖而衫半袖

C.袍的面料厚而衫的面料薄

D.袍有祛,而衫为宽大敞袖

题型:选择题

下列选项中,关于《法经》的表述正确的是( )

A.《法经》的作者是燕同的李悝

B.《杂法》和《捕法》多属于诉讼法的范围

C.《法经》是——部“诸法合体”而以刑为主的法典

D.《法经》是中国历史上第一部比较系统的封建成文法典

题型:选择题

断路器的灯光监视和音响监视的含义是什么?

题型:选择题

The common cold is the world’s most widespread illness, which is plagues that flesh receives.
The most widespread mistake of all is that colds are caused by cold. They are not. They are caused by viruses passing on from person to person. You catch a cold by coming into contact, directly or indirectly, with someone who already has one. If cold causes colds, it would be reasonable to expect the Eskimos to suffer from them forever. But they do not. And in isolated Arctic regions explorers have reported being free from colds until coming into contact again with infected people from the outside world by way of packages and mail dropped from airplanes.
During the First World War soldiers who spent long periods in the trenches, cold and wet, showed no increased tendency to catch colds.
In the Second World War prisoners at the notorious Auschwitz concentration camp, naked and starving, were astonished to find that they seldom had colds.
At the Common Cold Research Unit in England, volunteers took part in Experiments in which they gave themselves to the discomforts of being cold and wet for long stretches of time. After taking hot baths, they put on bathing suits, allowed themselves to be with cold water, and then stood about dripping wet in drafty room. Some wore wet socks all day while others exercised in the rain until close to exhaustion. Not one of the volunteers came down with a cold unless a cold virus was actually dropped in his nose.
If, then, cold and wet have nothing to do with catching colds, why are they more frequent in the winter Despite the most pains—taking research, no one has yet found the answer. One explanation offered by scientists is that people tend to stay together indoors more in cold weather than at other times, and this makes it easier for cold viruses to be passed on.
No one has yet found a cure for the cold. There are drugs and pain suppressors such as aspirin, but all they do is to relieve the symptoms.

Which of the following does not agree with the chosen passage

A. The Eskimos do not suffer from colds all the time.
B. Colds are not caused by cold.
C. People suffer from colds just because they like to stay indoors.
D. A person may catch a cold by touching someone who already had one.

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