问题 填空题

燃料乙醇的生产过程可由下图表示

(1)粉碎玉米的目的是___________。

(2)生产过程中为了检验淀粉水解是否完全,可使用的试剂的是_______________。

(3)步骤a的操作是__________。

A.蒸发    B.萃取    C.蒸馏    D.分液

(4)发酵产生的CO2纯度可达到99%,能回收利用,请举出它的两项用途_____________。

(5)以玉米等淀粉原料生产乙醇的化学反应可用下式表示:

(C6H10O5)n+nH2O→nC6H12O6 C6H12O6→2C2H5OH+2CO2

根据上述反应式,可以算出100 kg淀粉理论上可生产无水乙醇________kg。

答案

(1)加快反应速率  

(2)碘水  

(3)C  

(4)制饮料、制干冰、制取纯碱等(任填两种答案合理即可)  

(5)56.8

单项选择题
阅读理解

阅读理解。

     New archaeological discovers suggest that trade between Europe and Asia along the Silk Road probably

began in some form many countries earlier than once thought. The findings, coupled with a widening range

of scientific and historical research could add a fascinating new page to the epic of the Silk Road.

     The latest and most surprising discovery is pieces of silk found in the hair of and Egyptian mummy from

about 1000 BC, long before regular traffic on the Silk Road and at least one thousand years before silk was

previously thought to be used in Egypt. Other research may extend human activity along this route back even

further, perhaps a million years to the migration of human ancestors into eastern Asia.

     The official origin of East-West commerce along the road is usually placed in the late 2nd century BC

which was the agent of the Chinese Emperor Wu-di returned from a dangerous secret mission (使命) across

the desert into the remote high country of Central Asia. The agent, Zhang Qian, travelled as far as Afghanistan

back knowledge of even more distant lands such as Persia, Syria and a place known as Lijien, perhaps Rome.

Historians have called this one of the most important journeys in ancient times. His journey opened the way

for what have been thought to be the first indirect contacts between the ancient world's two superpowers,

China and Rome. Chinese silk, first traded to central Asian tribes for war horses and to the Parthians of old

Persia in exchange for acrobats and ostrich eggs, was soon finding its way through a network of merchants

to the luxury markets in Rome.

     But the new discoveries show that Chinese silk was apparently present in the West long before the Han

emperor started organized trade over the Silk Road. The research could change thinking about the early history

of world trade and provide insights into the mystery of just how and when Europe and the Mediterranean lands

first became aware of the glorious culture at the other end of Eurasia.

1. The word "coupled" in the first paragraph could best be replaced by _____.

A. produced

B. contributed

C. doubled

D. combined

2. The silk thread found in the hair of an Egyptian mummy suggests that _____.

A. Egyptians had probably travelled to China to buy silk

B. trade along the Silk Road began earlier than once thought

C. historical research often achieves fascinating results

D. new light can now be thrown on ancient trading practices

3. Until recently most historians believed that trade along the Silk Road _____.

A. originated in the 2nd century BC

B. extended human migration into eastern Asia

C. began a million years ago

D. primarily benefited the Egyptians

4. Historians have always considered Zhang Qian's mission important because they believe _____.

A. be brought back knowledge of Rome to the emperor

B. be discovered the Silk Road

C. be helped establish East-West trade

D. be travelled as far as Afghanistan