在pH=0的溶液中，能大量共存的离子组是（） A．Fe2+、Na+、Cl-、N

发布时间：2017-05-05 16:35 │ 来源：www.tikuol.com

题型：选择题

问题：

在pH=0的溶液中，能大量共存的离子组是（　　）

A．Fe²⁺、Na⁺、Cl^-、NO^-₃

B．K⁺、Ca²⁺、CH₃COO^-、HCO^-₃

C．Na⁺、Mg²⁺、NO^-₃、SO^2-₄

D．Ba²⁺、K⁺、Cl^-、SO^2-₄

考点：离子共存

题型：选择题

下列说法中正确的是（　　）

A．导体中没有电流通过时，电阻为零

B．导体中通过的电流越大，其对电流的阻碍作用越大，电阻越大

C．导体中通过的电流越小，其对电流的阻碍作用越大，电阻越小

D．导体的电阻跟导体中有无电流和电流的大小无关

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题型：选择题

完形填空。

When my son, Mark, was in the third grade, he saved all his pocket money for over three months
to buy holiday presents for those he loved. He had 1 twenty dollars.
The third Saturday in December, Mark said he had 2 his list and had his money in his 3 . I drove
him to a 4 supermarket. Mark picked up a hand basket and went off on his own 5 I waited 6 reading
a book at the front of the store. It 7 Mark over 45 minutes to choose his presents. When he came up
to the checkout(结账台), the smile on his face was truly 8 . The clerk rang up his purchase(在收款机
输入金额)as I politely looked at the other way. Mark kept 9 his budget and 10 into his pocket for his
money. 11 was not there! There was a hole in his pocket, but no money. Mark stood 12 the store holding
his basket, tears rolling down his cheeks. His whole body was 13 with his sobs. Then a(n) 14 thing
happened. A 15 shopping in the store came up to Mark. She knelt down and took him 16 her arms.
"You would do me the favor if you let me 17 your money," said the woman. "It would be the most
wonderful present you could ever give me. I only ask you could 18 . One day, when you grow up, I
would like you to find someone you can help. I know you feel as good about it 19 I do now when you
do help other people." Mark took the money, tried to dry his 20 and ran to the checkout as fast as he
could go.

( ) 1. A. collected
( ) 2. A. wrote
( ) 3. A. wallet
( ) 4. A. nearby
( ) 5. A. while
( ) 6. A. worriedly
( ) 7. A. spent
( ) 8. A. disappointing
( ) 9. A. in
( )10. A. put
( )11. A. It
( )12. A. at the front of
( )13. A. breathing
( )14. A. interesting
( )15. A. customer
( )16. A. by
( )17. A. reply
( )18. A. pass it on
( )19. A. that
( )20. A. sweat

B. gathered
B. made
B. purse
B. close
B. when
B. patiently
B. cost
B. upset
B. within
B. reached
B. There
B. at the back of
B. worrying
B. happy
B. clerk
B. with
B. return
B. pass it down
B. as
B. pocket

C. spared
C. had
C. pocket
C. near
C. though
C. politely
C. took
C. surprising
C. out of
C. turned
C. They
C. in the middle of
C. frightened
C. dramatic
C. stranger
C. in
C. give
C. continue it
C. what
C. presents

D. saved
D. shown
D. backpack
D. distance
D. as
D. regularly
D. needed
D. joyful
D. over
D. stretched
D. That
D. outside
D. shaking
D. amazing
D. guard
D. on
D. pay
D. keep it
D. which
D. tears

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题型：选择题

案例一　　（一）资料　　某公司于2003年年初购置设备一台，年初一次性投资160万元，预计该设备可以使用5年，采用直线法计提折旧，预计第5年年末净残值为10万元。其他有关情况如下：　　1. 该项设备投资计划可使公司每年增加净利润20万元；　　2. 该公司2002年税后可供分配利润数额为200万元；　　3. 该公司确定的目标资本结构是全部负债与股东权益比值为3∶5；　　4. 该公司一直采用剩余股利政策；　　5. 该公司平均资金成本为12%，2003年无其他投资机会，没有优先股发行。不考虑设备的安装调试期、公司所得税，也不考虑税法对设备折旧的影响，假定折旧从2003年1月开始计提。（复利现值系数PVIF12%，5=0.567，年金现值系数PVIFA12%，5=3.605。）　　（二）要求：根据上述资料，从下列问题的备选答案中选出正确答案。

根据该公司确定的目标资本结构，2002年税后可供分配利润中，用于该项设备投资的数额应是：

A．0

B．60万元

C．100万元

D．160万元

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（15分）某化学研究小组探究无水三草酸合铁酸钾K₃[Fe(C₂O₄)₃]受热分解的产物，并对所得气体产物和固体产物进行验证，按下图装置进行实验（夹持仪器已略去）。

（1）连接好装置后，加入药品前，应该进行的实验操作是________________(填操作名称)。

（2）实验开始时缓缓通入氮气，过一段时间以后，加热反应管A和E ，待反应完全后，停止加热，仍继续通氮气，直到反应管冷却。停止加热前是否需要先断开A、B的连接处和E、F的连接处？为什么？_______________________________________________________________。

（3）实验中观察到B中澄清石灰水变浑浊，则说明气体产物中有（写化学式）。

能证明分解产物中有CO气体生成的实验现象是。

（4）该小组同学查阅资料后得知，固体产物中不存在+3价Fe元素，而盐类物质只有K₂CO₃。

① 验证固体产物中钾元素存在的方法是，现象是。

② 研究小组为探究铁元素的存在形式，取A中充分反应后所得固体于试管中，加入足量蒸馏水，过滤、洗涤、干燥得到黑色粉末，取4.4g黑色粉末溶于足量稀硝酸中，收集到标准状况下NO气体1.12L通过计算判断黑色粉末的成分为（写化学式）。写出黑色粉末溶于足量稀硝酸发生反应的离子方程式。

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为响应市委、市政府“处处干干净净，人人彬彬有礼”的号召，小敏和同学们一起到街头巷尾用砂纸清除那些违章“小广告”；砂纸表面很粗糙，是为了______摩擦力（填“增大”或“减小”）．过了一会儿，小敏感觉砂纸发热，这是通过______方式来改变物体的内能的．

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在pH=0的溶液中，能大量共存的离子组是（ ） A．Fe2+、Na+、Cl-、N

问题：

在pH=0的溶液中，能大量共存的离子组是（） A．Fe2+、Na+、Cl-、N