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问题 选择题

下列各反应的离子方程式中,书写正确的是(        )

A． NaOH溶液与硫酸反应: 2H+ + 2OH- = 2H2O

B． FeCl3和Fe反应: Fe3+ +Fe = 2Fe2+

C．硫酸和氢氧化钡反应: H+ + SO42- + Ba2+ +OH- = H2O + BaSO4

D．氧化铜和稀盐酸反应: CuO + 2H+ = Cu2+ + H2O

答案

答案：D

A. NaOH溶液与硫酸反应:2H+ + 2OH- = 2H2O离子方程式未化简，应为H+ + OH- = H2O,A错；

B.  FeCl3和Fe反应:  Fe3+ +Fe = 2Fe2+电荷不守恒，应该为2Fe3+ +Fe = 3Fe2+；B错

C. 硫酸和氢氧化钡反应: H+ + SO42- + Ba2+ +OH- = H2O + BaSO4不符合物质的配比关系应为

2H+ + SO42- + Ba2+ +2OH- =2H2O + BaSO4,C错；

D、氧化铜和稀盐酸反应: CuO + 2H+ = Cu2+ + H2O，正确。

选D.

单项选择题

在计划内部审计业务时，所需记录的信息是：

A．完成既定的业务所需的资源。
B．所计划的业务工作能及时地完成。
C．预期的业务发现已得到清楚的辨识。
D．内部审计活动资源的使用有效率且有效果。
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填空题

Questions


·Read the following passage and choose the best word for each space.
Do you want to send an e-mail message to the White House
Good luck.
In the past, (26) President Bush — or at least those assigned to read his mail — what was (27) your mind it was necessary only to sit down at a personal computer connected to the lnternet and (28) a note to president@ whitehouse.gov.
But this week, Tom Matzzie, an online organizer with the A.F.L.-C.I.O., discovered that (29) with the White House had become a bit more (30) . When Mr. Matzzie sent an e-mail protesting (31) a Bush administration policy, the message was bounced back With an automated reply, saying he had to send it again in a new way.
Under a system (32) on the White House Website (33) the first time last week, those who want to send a message to President Bush must now (34) as many as nine Web pages and (35) a detailed form that starts by asking whether the message sender supports White House policy (36) differs with it.
The white House says the new e-mail system is an effort to be more responsive (37) the public and offer the administration "real time" access (38) citizen comments.
Completing a message to the president also requires (39) a subject from the provided list, then entering a full name, organization, address and e-mail address. (40) the message is sent, the writer must wait for an automated response (41) his message, (42) whether the addressee intended to send the message. The message is delivered to the White House only after the person using that e-mail address (43) it.
"Over (44) , it’s a very cumbersome process," said Jakob Nielsen, an authority on Web design. "It’s probably designed deliberately to (45) on their e-mail.\

A. fill withB. fill in C. fill up D. fill
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