问题 选择题

对于反应3Cl2+6NaOH ==5NaCl+NaClO3+3H2O,以下叙述正确的是

A.Cl2是氧化剂,NaOH是还原剂

B.被氧化的Cl原子和被还原的Cl原子的物质的量的比为5∶1

C.Cl2只是还原剂

D.每生成1mol的NaClO3转移5mol的电子

答案

答案:D

由3Cl2+6NaOH ==5NaCl+NaClO3+3H2O化合价变化知,6个Cl原子,一个从0价变为+5价,5个从0价变为—1价,知Cl2既是氧化剂又是还原剂,A、C均错误;被氧化的Cl原子和被还原的Cl原子的物质的量的比为1∶5,B错误;答案选D。

填空题
阅读理解

阅读理解。

     The first newspapers were written by hand and put up on walls in public place. The earliest daily newspaper

was started in Rome in 59 BC. In the 700's the world's first printed newspaper was published. Europe didn't

have a regularly published newspaper until 1609, when one was started in Germany.

     The first regularly published newspaper in the English language was printed in Amsterdam in 1620. In 1621,

an English newspaper was started in London and was published once a week. The first daily English newspaper

was the Daily Courant (每日新闻). It came out in March 1702.

     In 1690, Benjamin Harris printed the first American newspaper in Boston. But not long after it was first

published, the government stopped the paper. In 1704, John Campbell started The Boston Newsletter (波士顿新

闻通讯), the first newspaper published in the American colonies. By 1760, the colonies had more than thirty

daily newspapers. There are now about 1,800 daily papers in the United States.

     Today, as a group, English language newspapers have the largest circulation (发行量) in the world. But the

largest circulation for a newspaper is that of the Japanese newspaper Asahi Dhimbun (朝日新闻). It sells more

than 11 million copies every day.

1. The first daily newspaper came out in _____. [ ]

A. 59 BC

B. 700's

C. 1609

D. 1620

2. The first regular published newspaper in Europe was printed in _____. [ ]

A. England

B. Germany

C. France

D. Sweden

3. The first printed newspaper in America came out in _____.[ ]

A. Washington

B. New York

C. Boston

D. New Orleans

4. Today there are about _____ daily newspaper printed in the United States. [ ]

A. 1621

B. 1704

C. 1760

D. 1800