问题 选择题

下列解释不科学的是(  )

A.在溶洞中,当溶解在水里的Ca(HCO32发生分解,析出固体(在洞顶或洞底),日久天长便形成了钟乳石

B.长期盛放NaOH溶液的试剂瓶不易打开,是因为NaOH与玻璃中的SiO2反应生成一种有粘性的Na2SiO3导致瓶塞与试剂瓶粘连不易打开

C.“通风橱”是利用排风扇将橱内废气直接排放到室外的装置,它是一种不完善的防污设施

D.高压氧舱可治疗煤气中毒,原因是和血红蛋白结合的CO跟氧气反应生成无毒的二氧化碳

答案

答案:D

推断题
阅读理解

Life gets noisier every day and very few people can be free from noise of some sort or another. It doesn't matter where you live--in the middle of a modern city, or a faraway village--the chances are that you' ll be disturbed by jet planes, radios, oil - powered engines, etc. We seem to be getting used to noise, too. Some people feel quite lonely without background music while they' re working.

Scientific tests have shown that total silence can be a very frightening experience for a human being. However, some people enjoy listening to pop music which is very loud, and this can do harm to their eardrums(耳鼓). The noise level in some discos is far above the usual safety level for heavy industrial areas.

One recent report about noise and concentration(专心) suggested that although a lot of people say that any noise disturbs their concentration, what really influences their ability to concentrate is a change in the level of noise. It goes on to say that a background noise which doesn't change too much(music, for example) may even help people to concentrate.

小题1:According to this passage, the noise pollution         .

A.has become the worst in the countryside

B.has become better in big cities

C.has spread from cities to villages

D.has been controlled in modern cities小题2:Some people have their hearing harmed        .

A.while listening to pop music

B.in complete silence

C.when speaking loudly

D.while watching TV小题3:Scientists have discovered that what prevents people from concentrating on something is        .

A.all kinds of noise

B.changes in the level of noise

C.background noise

D.popular music