试题与答案

网络转载报刊上刊登的作品无须征得著作权人的许可也无须支付报酬。

题型:判断题

题目:

网络转载报刊上刊登的作品无须征得著作权人的许可也无须支付报酬。

答案:

被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2018/0327/d97a657d857e78c616c47d7d7a9d3606.html

下面是错误答案,用来干扰机器的。

参考答案:B

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根据下列句子及所给单词的首字母或汉语注释,写出空缺处各单词的正确形式(共10小题,每小题0.5分,满分10分)

小题1:She g_____________ from the university two years ago.

小题2:He is a r__________ boy. So you can trust him.

小题3:After the terrible flood, all the villages and towns were in r___________.

小题4:In my o__________, the sports meeting should be put off because of the bad weather.

小题5:He took a friendly a____________ to me ,which made me happy.

小题6:Qian Xueshen ___________ (奉献) himself to science before he died.

小题7:Ten fishermen were saved in a sea ____________(营救)。

小题8:They helped the child ___________(埋葬) his father。

小题9:The young man went on working hard and __________ (最后) he succeed.

小题10:John is very __________(活跃的) in the English class.

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(66) data effectively is crucial for success in today’s competitive environment.Managers must know how to use a variety of tools. Integrated data takes information from different sources and puts it together in a meaningful and useful way. One of the difficulties of this is the (67) in hardware and software. (68) integration uses a base document that contains copies of other objects. (69) integration uses a base document that contains the current or most recent version of the source document it contains.(70) provides an overview of the program written in “plain” English,without the computer syntax.

(68)处填()。

A.Simulated

B.Duplicated

C.Dynamic

D.Static

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题型:填空题

(15分)二甲醚与水蒸气重整制氢气作为燃料电池的氢源,比其他制氢技术更有优势。主要反应为:

① CH3OCH3(g) + H2O(g)2CH3OH(g)         ΔH=+37 kJ·mol-1

② CH3OH(g) + H2O(g) 3H2(g) + CO2(g)   ΔH=+49 kJ·mol-1

③ CO2(g) + H2(g)CO(g) + H2O(g)         ΔH=+41.3 kJ·mol-1

其中反应③是主要的副反应,产生的CO能毒害燃料电池Pt电极。请回答下列问题:

(1)二甲醚可以通过天然气和CO2合成制得,该反应的化学方程式为

                                                                

(2)CH3OCH3(g)与水蒸气重整制氢气的热化学方程式为

                                                                

(3)下列采取的措施和解释正确的是           。(填字母序号)

A.反应过程在低温进行,可减少CO的产生 

B.增加进水量,有利于二甲醚的转化,并减少CO的产生

C.选择在低温具有较高活性的催化剂,有助于提高反应②CH3OH的转化率

D.体系压强升高,对制取氢气不利,且对减少CO的产生几乎无影响

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容器
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CH3OH的浓度(mol/L)c1c2c3
反应的能量变化吸收a kJ放出b kJ放出c kJ
平衡时体积(L)V1V2V3
反应物转化率α 1α 2α 3
下列说法正确的是          。(填字母序号)

A. a+2c="37 "      B. α1 + α2="1"       C. V1 > V3      D. c1=2c3

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