问题 选择题

物质在氧气中燃烧的实验现象描述正确的是(  )

A.硫在氧气中燃烧,发出微弱的淡蓝色火焰,产生无色刺激性气味的气体

B.红磷在氧气中剧烈燃烧,发出耀眼白光,有大量白色气体生成

C.木炭在氧气中燃烧,有二氧化碳气体生成

D.细铁丝在氧气中剧烈燃烧,火星四射,有黑色固体生成,并放出大量的热

答案

A、硫在空气中燃烧,发出微弱的淡蓝色火焰,在氧气中燃烧,发出明亮的蓝紫色火焰,都放出热量,都产生一种具有刺激性气味的气体,故A错误;

B、红磷在氧气中燃烧时,能够产生大量的白烟,而不是气体,故B错误;

C、木炭在氧气中燃烧,有二氧化碳气体生成,不是现象,故C错误;

D、铁丝在氧气中剧烈燃烧,火星四溅,放出热量,生成一种黑色粉末,黑色粉末是四氧化铁,故D正确.

故选D.

阅读理解

People today expect to be examined when they enter a doctor's office. At least they expect their blood pressure and temperature to be measured. However, as recently as two hundred years ago, a doctor's treatment depended on talking with patients. In general, the communication between doctors and their patients was the most important part of medical methods. The modem age of medicine began with the stethoscope ,an instrument for listening to patients heartbeat and breathing. Before that, a doctor did not touch a patient. In fact, there was no such things as a medical examination.

The stethoscope──and all other medical instruments──-had a serious effect, on the practice of medicine. Doctors became better at finding the medical problems. More lives were saved. At the same time, doctors gave less importance to the communication between patients and doctors. Some doctors actually stopped talking to their patients. It is easy to understand why some sick people thought themselves as broken machines.

1. A stethoscope can be used to________.

A. check health conditions     B. cure some illness

C. measure temperature       D. treat heart disease

2. Doctors gave less importance to the communication between patients and doctors mainly because________.

A. modern medical instruments were used

B. they could cure more diseases and save more lives

C. they had much more medical experience than before

D. they were too busy to have time to talk with patients

3. Some sick people thought of themselves as broken machines, which suggested that_______.

A. modern doctors should treat their patients as machines

B. the level of the treatment was greatly improved

C. they thought they were useless just like broken machines

D. they were not satisfied with the manner in which doctors treated them

4. The best title for this passage should be________.  

A. Medical Methods of Two Hundred Years Ago

B. The Development of Medical Methods

C. The Modem Age of Medicine

D. The Use of the Stethoscope

判断题