25℃时,弱酸的电离平衡常数如下表,下列表述错误的是 弱酸CH3COOHHCNH

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问题:

25℃时,弱酸的电离平衡常数如下表,下列表述错误的是

弱酸CH3COOHHCNH2CO3
K1.8×10-54.9×10-10K1=4.3×10-7   K2=5.6×10-11
A.CN+H2O+CO2→HCN+HCO3

B.相同温度时三种浓度相同溶液,pH关系:Na2CO3> NaCN > CH3COONa

C.等体积、等物质的量浓度的CH3COOH和Na2CO3混合反应后:

c(Na+)>c(HCO3)>c(CH3COO)>c(OH)>c(H)

D.amol/L HCN与bmol/L NaOH等体积混合溶液c(Na+)>c(CN),则a一定小于b

考点:弱电解质电离的影响因素弱电解质的电离度弱电解质的电离
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.阅读下面文字,把文中拼音所表示的汉字和加点字的注音依次填在方格内。(2分)
美人蕉,城乡皆可看到。美人蕉有婀nuó( )之姿,无论在城市的公园里还是在乡村的篱笆旁,都猩( )红似火,灿烂耀眼,含情带笑,俨( )若美人。印度大诗人泰戈尔说:“生如夏花之xuàn( )烂……”这诗句,最适用于美人蕉。
(选自胡弦《菜与花》)
  
 
 
 
 
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为了积极响应教育部的精神,各地纷纷推出免费义务教育方案,凡是处于义务教育阶段的中小学生都享受此项政策。这项政策体现了我国义务教育具有                 特点。 [     ]

A.强制性

B.固定性

C.公益性

D.义务性

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Fear plays no part in this latest problem.“I’m not afraid I'll lose my children.I won't lose my children. We live together, and nothing, nothing,”she repeats, her voice rising when speaking to John's lawyer, “will stop me from being with my children. A law? Year, right. Don't disturb me when it comes to my children. You are never going to win. If John wants to see them, I cannot stop him. He's their father­­—I want them to see him! However, his visit in his present condition will disturb the children's stable (稳定的) life.”

John, who has spent much of his time in California recently, has only hired a house for himself in Pennsylvania, according to his lawyer. "If he'd like to stick to a regular life, I'd be more than happy to do that," Jane says. "The best thing for any child of a divorced (离婚的) parent is a stable life. I want nothing more than for him to set up a stable life for himself, so that he can be part of making our children's lives more stable. "

While matters of money and care won't be settled for weeks, Jane hardly puts her life on hold. Last week the ABC network announced that Jane would return with her own show, Twist of Jane, in which she gives advice to other moms.Jane and her eight children will also return to ABC in a series  of  Jane Plus 8 specials showing them on various adventures.It’s a rest for Jane.who insists that she needs her new,busy life to provide for her family.“I have to lead such a life.and I’m thankful that I’ve built it to the top where now I can support my children.”she says.

And  whether a bellicose(好斗的)dance judge or a bellicose former wife,Jane plans to keep  0n facing attacks on her.  “Some people try to knock me down—only to make me more fierce,more protective,more determined to do better,”she says.“Go ahead,take me on.This will just make me stronger.”

1  According to Jane in the first paragraph,the low____________

A. can’t take her children away from her        B. can’t do anything with the case

C. will best settle the problem                D.  will disturb her children

2 . What does “to do that” refer to in the second paragraph?

A. To live with John.                    B.To hire a house for John.

C.To allow John to see the children         D.To ask John to set up a regular life.

3. What does the underlined sentence in the third paragraph mean?

A.Jane’s life is very difficult.         B.Jane continues to live as usual.

C.Jane almost can’t control her lire      D.Jane works very hard to live a happy life.

4 . Which word can best describe Jane?

A. Proud.    B.Fierce.    C.Determined.     D.Independent

题型:选择题

石灰石(主要成分碳酸钙)与稀盐酸反应生成氯化钙、水和二氧化碳:______.

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综合布线作为计算机网络的传输通道,其传输性能等级直接影响网络的传输速度。由于10Gbps布线系统工作的频率范围扩展到500MHz,这样工作频率的增高带来了邻近电缆和模块间产生的串绕问题,因此对10Gbps布线进行测试时,需要关注___13___指标以判断这种串绕的严重程度。通常,减少这种串绕的解决方法不包括___14___。

14()

A.适当降低交换机端口的信号发射功率

B.使用不同于常规圆形设计的电缆

C.增大配线架(或墙壁面板上模块)之间的间隔

D.使用较厚护皮的电缆

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