问题 填空题

有X、Y、Z、W、M五种短周期元素,它们满足如下关系:①原子序数依次增大;②ZX4++WX-=ZX3+X2W,且反应物和产物中各微粒的电子总数与M+相等,均为10个;③Z2与YW分子中质子数相等.回答下列问题:

(1)ZX4+的电子式:______;实验室中MWX溶液的保存方法是:______

(2)由X、Y、Z、W四种元素共同组成的离子化合物A,其原子个数比为5:1:1:3,则A的水溶液与足量的MWX溶液反应的离子方程式为:______

(3)M2W2投入足量Na2S溶液中,生成浅黄色沉淀的化学方程式为:______.

答案

根据ZX4++WX-═ZX3+X2W,且反应物和产物中各微粒的电子总数均为10个电子,则ZX4+为NH4+,WX-为OH-

ZX3为NH3,X2W为H2O;M+电子数与NH4+、OH-、NH3、H2O相等,则M+为Na+;所以M为Na元素,X为H元素,Z为N元素,W为O元素;由于Z2与YW分子(YW分子为CO)中质子数相等则Y为C元素.

(1)ZX4+为NH4+,电子式为

M为Na元素,X为H元素,W为O元素,则MWX为NaOH,易吸收水和空气中的二氧化碳反应,氢氧化钠能与二氧化硅反应生成硅酸钠,硅酸钠是矿物胶,不能用玻璃塞,则应密闭保存在带橡胶塞的试剂瓶中.

故答案为:

;密闭保存在带橡胶塞的试剂瓶中.

(2)由X、Y、Z、W四种元素共同组成的离子化合物A,其原子个数比为5:1:1:3,则A为NH4HCO3,MWX为NaOH,NH4HCO3溶液与足量NaOH溶液反应的离子方程式为NH4++HCO3-+2OH-=NH3•H2O+CO32-+H2O.

故答案为:NH4++HCO3-+2OH-=NH3•H2O+CO32-+H2O.

(3)M2W2是Na2O2,Na2O2有强氧化性,Na2O2投入足量Na2S溶液中,生成浅黄色沉淀是S,反应的化学方程式为:

Na2O2+2H2O+Na2S=4NaOH+S↓.

故答案为:Na2O2+2H2O+Na2S=4NaOH+S↓.

阅读理解

阅读理解。                        

     One day in early March of 1993,Pauline and Tom Nichter and their 11-year-old son Jason,were shopping for a toy in Buena Park,CA.Suddenly,Panline saw a wallet lying on the floor.When she looked inside,

she found $200.The family,homeless and without work,knew that could change their lives.But they took

the wallet to the nearby police station and turned it in.The wallet was found to have some other pockets,

and more money in-over $2000!The police called the man who lost the wallet to pick it up.The man

thanked the Nichters and shook their hands,but didn't reward them.Luckily for the family,a TV news

reporter filmed the story.People from all over the world heard the story and sent them letters,money and

even jobs.A businessman even let them live in his house for free for six months.So far,the family has

received over $100 000.Now the Nichter's future is bright.

1.The best title(标题)of the reading would be_____________.

A.Money is Everything

B.From Poor to Rich

C.A kind Businessman

D.A Lost Wallet and the Police

2.Who found out the secret of the wallet?

A.The police.

B.Jason.

C.Someone else in the shop.

D.The man who lost the wallet.

3.From the reading,we know many people_____________.

A.work hard to change their lives

B.are friendly to the loser

C.are ready to help others

D.often have good luck

4.The words “reward them” in the reading mean_____________.

A.speak to the Nichters

B.give something to the Nichters

C.pay the police

D.meet the news reporters

5.Which of the following is true about the Nichters?

A.They got lots of money from a reporter.

B.They made friends with the loser of the money.

C.They posted letters to the people all over the world.

D.They became known to many people.

单项选择题