问题 填空题

老师用下图所示装置为同学们做了一个兴趣实验。A装置中盛有二氧化锰黑色粉末,B装置中盛有足量的澄清石灰水,C装置中盛有足量的稀盐酸,气球中装有少量的碳酸钠粉末。

资料:碳酸钠粉末与稀盐酸能发生化学反应,

(1)打开分液漏斗的活塞和玻璃塞,使A装置与大气相通,将气球中的碳酸钠粉末全部倒入稀盐酸中,可以观察到C装置中的现象是__________。

(2)待上述反应结束后,从分液漏斗注入足量的过氧化氢溶液,关闭活塞和玻璃塞,A装置中发生反应的化学方程式为__________。

(3)在整个实验过程中,B装置中的现象是__________。

(4)C装置中气球的作用是__________(填字母)。

a. 收集纯净气体 b. 添加固体药品 c. 调节C装置容积   d. 控制气体总量

答案

(1)有无色气泡逸出,白色固体消失,气球微微鼓起

(2)

(3)溶液先变浑浊,后有部分变浑浊的液体被压入C装置中

(4)bc

(1)碳酸钠加入盐酸中会产生大量的气体,故答案为:碳酸钠粉末溶解,有大量气泡产生,气球微微鼓起.

(2)根据反应物是二氧化锰和双氧水,来书写化学方程式,故答案为:2H2O22H2O+O2↑.

(3)碳酸钠和盐酸反应会生成二氧化碳使C中气压增大,将气体压入B中,二氧化碳会与石灰水反应出现白色沉淀,A中产生的氧气又会将B中的液体压入C中,故答案为:澄清石灰水变浑浊,B中的液体进入C中,且浑浊溶解.

(4)A中的二氧化锰与双氧水反应会产生大量的气体,使整个装置中气压增大,同时容纳碳酸钠粉末.故选:bc.

单项选择题
阅读理解

Two Christmas traditions have come under attack in recent years from environmentalists: Christmas cards and Christmas trees.

Paper cards are seen as wasteful and, for some people, going card-free is another way of going green. They also argue that in a world of e-mail, Skype, Facebook and Twitter, people are in touch all the time anyway; they no longer need the yearly card that connects them with long lost friends. If you want to send Christmas greetings, there are free e-cards, which get the job done with no postage or wasted paper.

However, especially for people who didn’t grow up with e-mail, there is something missing from a Christmas e-mail. The first Christmas cards appeared in London in 1843 and were designed by the same man who had introduced the world’s first postage stamp three years earlier. His name was Sir Henry Cole.

They rose in popularity throughout the 20th century. Many people sent cards that were sold for charity. The most famous of these are the ones sold for UNICEF. In the UK this year, in the three weeks before Christmas, the post office expects to handle 100 million cards every day. Environmental awareness also means that nowadays many people recycle their cards; this helps raise money to plant more trees, as well as recreating more paper.

When we think of trees at Christmas, there is one that immediately springs(跃入)mind---the evergreen tree that people decorate with ornaments and place their presents under. The custom dates back almost a thousand years to Germany. Nowadays 33 to 36 million Christmas trees are produced in America and 50 to 60 million in Europe each year. Some trees are sold live with roots and soil so people can plant them later and reuse them next year.

Some people prefer artificial trees as they are reusable and much cheaper than their natural alternative. However, environmentalists point out that they are made from petroleum (石油) products and so have many pollution issues.

小题1:What is the main idea of the article?

A.To introduce the history of two typical Christmas traditions.

B.To explain the debate about some Christmas traditions.

C.To analyze how two Christmas traditions grew in popularity.

D.To point out the problems caused by celebrating Christmas.小题2:What does the underlined word “They” in the fourth paragraph probably mean?

A.Many people

B.Christmas e-mails

C.Postage stamps

D.Christmas cards小题3:Some people suggest getting rid of paper cards because     .

a. they cannot be recycled         b. they are not environmentally friendly

c. they are mostly sold for charity  d. the e-cards have many advantages over them

e. they are not as necessary as they used to be for people

A.a, b, d

B.a, c, d

C.b, d, e

D.b, c, e小题4:What can we conclude from the article?

A.The first Christmas cards were designed earlier than the world’s first stamps.

B.This year has seen a dramatic drop in Christmas card sales.

C.Environmentalists advise people to buy cards that are sold for charity.

D.Growing environmental awareness is encouraging people to recycle their cards.小题5:Which of the following statements in TRUE according to the article?

A.There is always a wider Christmas tree market in America than in Europe.

B.The custom of decorating Christmas trees first appeared in Britain.

C.Some people prefer to buy live trees that can be reused next year.

D.Artificial trees are better than natural ones in all aspects.