问题 实验题

某同学用如图所示的装置进行铜与浓硫酸反应的实验。

请回答:

(1)铜与浓硫酸反应的化学方程式是________________________

(2)实验过程中,观察到品红溶液________________,石蕊溶液________________,说明SO2________(填选项)。

a. 有氧化性    b. 有还原性    c. 有漂白性    d. 水溶液显酸性

(3)为进一步确认产生的气体是二氧化硫气体,还应补充的操作是________________

(4)结合离子方程式说明试管D中氢氧化钠溶液的作用是______________________

(5)把试管A中的液体冷却后慢慢倒入盛有水的烧杯里,观察到溶液呈________色,说明铜元素被氧化生成了________离子。

答案

(11分)(1)Cu+2H2SO4(浓)CuSO4+SO2↑+2H2O(2分)

(2)褪色(1分)   变红(1分)    cd(2分) (3)加热褪色后的品红溶液(1分)

(4)吸收逸出的SO2,SO2+2OH=SO32+H2O(2分)

(5)蓝(1分);铜(1分,写成Cu2+给分)

题目分析:(1)浓硫酸是氧化性酸,因此铜与浓硫酸反应的化学方程式是Cu+2H2SO4(浓)CuSO4+SO2↑+2H2O。

(2)还原产物SO2具有漂白性,所以SO2通入到品红溶液中,溶液红色退去;SO2溶于水生成亚硫酸,溶液显酸性,所以通入到石蕊试液中,溶液显红色。

(3)由于SO2的漂白是不稳定的,加热后又能恢复到用来到颜色,所以为进一步确认产生的气体是二氧化硫气体,还应补充的操作是加热褪色后的品红溶液。

(4)SO2有毒,属于大气污染物,所以氢氧化钠溶液的作用是吸收逸出的SO2,反应的离子方程式是SO2+2OH=SO32+H2O。

(5)在反应中铜是还原剂,失去电子,被氧化生成硫酸铜,所以把试管A中的液体冷却后慢慢倒入盛有水的烧杯里,观察到溶液呈蓝色。2的性质以及尾气处理等

点评:该题是高考中的常见考点,属于中等难度的试题。试题基础性强,紧扣教材,有利于巩固学生的基础,提高学生的综合实验能力,也有利于培养学生的逻辑思维能力和环境保护意识,难度不大。

阅读理解

Greg Woodburn, a university student, spends a lot of time cleaning sports shoes. Some of them once belonged to him; some belonged to his friends. But soon the shoes will have new owners, poor children in the USA and 20 other countries, thanks to Greg’s Share Our Soles(鞋底) (S.O.S) charity. 

Greg was a high school running star in a small town in California. He had to stop running for months because his knee was injured. “I started thinking about all the things I got from running, the health, the friendships and the confidence.” he says. And I realized there are children who don’t even have shoes.

Greg collected his own sports shoes and then called his friends and the town. His aim was to have 100 pairs by Christmas 2006. When the number climbed to more than 500 pairs. Greg know that he could collect sports shoes all year round.

Now he has set up collection boxes in his town. So far, S.O.S has collected and donated more than 3,000 pairs of shoes. And Greg has cleaned almost all of them. “People think of it as duty work,” he says, “but I like doing it, because I feel happy when I’m doing it. It’s not work I want to pass on to someone else.”

In just three years, Greg has started three branches(分部) of S.O.S and there are more and more sports shoes.

For many poor children who have received the shoes mean opportunity. Two young boys in southern California used to go to school on alternate days(隔日) because they both shared a pair of shoes. They were too big for one boy and too small for the other. Thanks to S.O.S, each brother received his own pair of shoes. The boys now go to school every day. When they graduate, they say they will help others, just as Greg helped them.

小题1:Who will Greg donate these sports shoes to?

_____________________________________________

小题2:From running Greg got health, friendships and confidence, and what did he realize?

_____________________________________________

小题3:How many pairs of shoes has S.O.S collected and donated so far?

_____________________________________________

小题4:Why does Greg like to clean the donated shoes?

__________________________________________________

小题5:What did the two boys in southern California learn from Greg?

___________________________________________________

选择题