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问题 选择题

将3.48gFe3O4完全溶解于100mL0.5mol/L硫酸中，然后加入K2Cr2O7溶液25mL ，恰好使溶液中Fe2+全部转化为Fe3+,Cr2O72-全部还原为Cr3+，则K2Cr2O7溶液的物质的量浓度为

A．0.05mol/L

B．0.1mol/L

C．0.2mol/L

D．0.3mol/L

答案

答案：B

3.48gFe3O4完全溶解于100mL0.5mol/L硫酸中，会得到0.015molFe2＋

14H＋＋6Fe2＋＋Cr2O72－=6Fe3＋＋2Cr3＋＋7H2O

6      1

0.015   X

列比例式得到X=0.0025mol，C(K2Cr2O7)= 0.1mol/L  故选B。

单项选择题

People are indulging in an illusion whenever they find themselves explaining at a cocktail(鸡尾酒 ) party, say, that they are "in computers," or " in telecommunications," or "in electronic funds transfer". The implication is that they are part of the high-tech world. Just between us, they usually aren’t. The researchers who made fundamental breakthroughs in those areas are in a high-tech business. The rest of us are (11) of their work. We use computers and other new technology components to develop our products or to organize our affairs. Because we go about this work in teams and projects and other tightly knit working group(紧密联系在一起的工作小组 ), we are mostly in the human communication business. Our successes stem from good human interactions by all participants in the effort, and our failures stem from poor human interactions.
The main reason we tend to focus on the (12) rather than the human side of work is not because it’s more (13) , but because it’s easier to do. Getting the new disk drive installed is positively trivial compared to figurine out why Horace is in a blue funk(恐惧)or why Susan is dissatisfied with the company aver only a few months. Human interactions are complicated and never very crisp(干脆的,干净利落的) and clean in their effects, but they matter more than any other aspect of the work.
If you find yourself concentrating on the (14) rather than the (15) , you’re like the vaudeville character(杂耍人物)who loses his Keys on a dark street and looks for them on the adjacent street because, as he explains, "The light is better there!\

A．technical

B．classical

C．social

D．societal
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多项选择题

可以在任一营业网点办理的手机银行业务有（）

A.客户账户绑定维护

B.客户功能设定

C.口挂

D.撤口挂

E.支付密码重置

F.登录密码重置
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