试题与答案

(8分)盐酸、硫酸和硝酸是中学阶段常见的三种强酸。请就三者与金属铜的反应情况,回

题型:填空题

题目:

(8分)盐酸、硫酸和硝酸是中学阶段常见的三种强酸。请就三者与金属铜的反应情况,回答下列问题:

(1)①在100mL 1 8 mol·L-1的浓硫酸中加入过量的铜片,加热使之充分反应,产生的气体在标准状况下的体积可能是           

A.40.32L

B.30.24L

C.20.16L

D.6.72L②有同学提出,若使上述反应①中剩余的铜片继续溶解,可向其中加入硝酸钠,请判断该方案是否可行?若不可行,请说明原因。若可行,请写出反应的离子方程式:                                               

(2)若将6.4g铜粉与一定量浓硝酸反应,当铜粉完全溶解时,生成气体(NO、NO2)共2.24L(标准状况),则反应中所消耗的硝酸的物质的量为            

(3)某同学向浸泡铜片的稀盐酸中加入H2O2后,铜片溶解,并且该反应的产物只有氯化铜和水。该反应的化学方程式为:                     

答案:

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题型:阅读理解

I never thought I would have a life­changing experience at Wal­Mart.

Although my thoughts were only on speed,the checkout line I was standing in wasn’t moving as quickly as I wanted,and I glanced toward the cashier.

There stood a man in his seventies,wearing glasses and a nice smile.I thought,well,he’s an old guy!

For the next few minutes I watched him.He greeted every customer before scanning the items.Sure,his words were the usual,“How’s it going?” But he did something different—he actually listened to people.Then he would respond to what they had said and engage them in brief conversation.

I thought it was odd.I had grown accustomed to people asking me how I was doing simply out of robotic conversational habit.After a while,you don’t give any thought to the question and just mumble something back.I could say,“I just found out I have six months to live,” and someone would reply,“Have a great day!”

But that wasn’t the end.

He gave them the change,walked around the counter,and extended his right hand in an act of friendship.He looked the customers in the eyes.“I sure want to thank you for shopping here today,” he told them.“You have a great day.Bye­bye.”

The looks on the faces of the customers were priceless.There were smiles and some sheepish grins.All had been touched by his simple gesture—and in a place they never expected.They would gather their things and walk out,smiling.

Of course,he did the same to me and I got to know his name,Marty.

Who was that guy?It was as if Sam Walton had come back from the dead and invaded this old guy’s body.

I had never walked away from that shop feeling like that.

小题1:The checkout line the writer was standing in moved slower than expected because ________.

A.the cashier couldn’t work as fast as others

B.there were some big purchases

C.the cashier did more than scanning the items

D.the writer was not patient enough小题2:According to the writer,when common people ask you “How’s it going?” ________.

A.they don’t really care what you may answer

B.they are just practicing their conversation ability

C.they are inquiring about your private information

D.they don’t expect to hear any negative answers小题3:What was most customers’ reaction to Marty’s behaviors?

A.They thought it priceless.

B.They were in some way moved.

C.They thought it awful and odd.

D.They felt somewhat offended.小题4:What does the writer intend to express through the text?

A.Our everyday life is always full of surprises.

B.Most customers enjoy being treated this way.

C.Being different is a good way of doing business.

D.A little positive action can make a big difference.

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