问题 问答题

(1)甲元素位于元素周期表的第3周期ⅢA族,乙元素的原子结构示意图为

①写出甲、乙两种元素符号:甲______、乙______.

②甲元素原子核外有______个电子层.

③甲元素的金属性(即原子失电子的能力)比乙元素______(填“强”或“弱”).

(2)过氧化氢在适当条件下能发生分解反应:2H2O2=2H2O+O2

现进行如下实验探究:在甲、乙两支大小相同的试管中各装入3mL5%的过氧化氢溶液,再向其中的甲试管中加入少量MnO2粉末.请给合实验现象填写下列空白.

①实验目的:研究______(反应条件)对过氧化氢分解反应速率的影响.

②实验现象:______(选填“甲”或“乙”)试管中反应更剧烈,迅速放出无色气体.

③实验结论______.

答案

(1)甲元素位于元素周期表的第3周期ⅢA族,则甲为Al元素,根据乙元素的原子结构示意图知,乙是Na元素,

①甲是Al、乙是Na元素,故答案为:Al;Na;

②元素所在的周期数与其电子层数数值相等,所以甲元素原子核外有3个电子层,故答案为:3;

③同一周期元素中,元素的金属性随着原子序数的增大而减弱,钠和铝属于同一周期,且钠的原子序数小于铝,所以铝的金属性小于钠,故答案为:弱;

(2)①根据实验的不同点确定实验目的,两个实验中不同点是:一个有催化剂、一个没有催化剂,所以其实验目的是研究催化剂对化学反应速率的影响,故答案为:催化剂;

②催化剂能加快反应速率,所以甲试管中反应较剧烈,故答案为:甲;

③根据实验现象知,有催化剂的反应速率比没有催化剂的反应速率快,由此得出催化剂能改变反应速率,故答案为:催化剂能改变反应速率.

阅读理解

C

Snoopy and Lou were robbers. Half a year ago, they decided to plan another bank robbery. It was to be their last one. Then they would give up this business and live a comfortable life. The job was so well done that the judge who sent them to prison for fifteen years each said it was the cleverest robbery of the century, and what a pity it was that their car had used up its petrol not far from the bank.

After they were in prison for a few weeks, Snoopy and Lou decided to escape. Soon they worked out a plan as good as any they had ever made. Even the smallest points were considered carefully. They planned as a team because they lived in the same room, and because the guards, who had a great deal of respect for the famous robbers, left them very much alone. They decided the quickest and safest way to escape was to squeeze themselves along a drain form their present workplace in the prison to a quiet country road on the other side of the prison wall.

The great day arrived, and the pair started along the drain. With great difficulty, they squeezed themselves along for what seemed ages. In half an hour , they could see daylight. When they got out, the men were so pleased with themselves at their success that they sloped each other on the back. It was only then that they realized they were not alone. They looked around, they found themselves facing thirty astonished policemen, who were carrying musical instruments of various sorts. The next morning, the same judge seemed very sorry as he told Snoopy and Lou that the plan of the prison drain system, which they had studied so carefully, was more than twenty years old, and that the quiet country road was no longer there. The drain now led directly to the parade ground where the police band had just finished practicing when the two robbers appeared before them.

64.What was Snoopy and Lou’s plan to escape from the prison?

A.They planned to run away while working

in the prison workplace.

B.They planned to climb over the prison wall, on the other side of which was a quiet country road.

C.They planned to crawl along the drain which led to a country road

D.They planned to get to the parade ground through the drain which was empty when the police band was not practicing.

65.Snoopy and Lou failed in their plan to escape because_________.

A.they did not play well before hand

B.they were not quick enough in their action

C.the policemen had been keeping a watchful eye on them

D.the map of the prison drain system they used was out of date

66.According to this article, which of the following statements is true?

A.When Snoopy and Lou went out of the drain, thirty policemen were waiting for them.

B.When Snoopy and Lou found themselves facing thirty policemen, they turned round and ran in the direction of the country road.

C.The policemen caught Snoopy and Lou by chance

D.The policemen were frightened more than surprised when the two robbers suddenly appeared before them

67.It seemed the judge________.

A.admired Snoopy and Lou for their cleverness

B.felt very proud to try the two famous robbers for their crime

C.was very angry at Snoopy and Lou’s breaking the law again and again

D.was sad at Snoopy and Lou’s breaking the law again

多项选择题