运用化学反应原理研究氮、碳、硫等单质及其化合物的反应有重要意义。 (1)氨在国民

题型:填空题

问题:

运用化学反应原理研究氮、碳、硫等单质及其化合物的反应有重要意义。

(1)氨在国民经济中占有重要地位。合成氨工业中,合成塔中每产生2mol NH3,放出92.2kJ热量。

①若起始时向容器内放入2mol N2和6mol H2,达平衡后放出的热量为Q,则Q(填 “>”、“<”或“=”)                184.4 kJ。

②已知

1mol N—H键断裂吸收的能量等于            kJ。

(2)硫酸的年产量可以用来衡量一个国家的化工生产能力。工业生产硫酸的流程中存在反应:2SO2(g)+O2(g)2SO3(g)。反应体系中SO3的百分含量和温度的关系如下图所示(曲线上任何一点都表示平衡状态)。根据图示回答下列问题:

①该反应的          0(填“>’或“<”)。

②下列说法正确的是

a.若在恒温、恒压条件下向上述平衡体系中通入氦气,平衡不移动

b.在D点时,v>v

c.B点、C点反应的平衡常数分别为K1、K2,则K1<K2

d.在A点时,消耗1mol SO2必定同时消耗1mol SO3

(3)过度排放CO2会造成温室效应。

①最近科学家提出“绿色自由”构想能把空气中的CO2转变为可再生燃料甲醇。甲醇可制作燃料电池,写出该电池负极反应式(电解液为KOH溶液)                  

②CO2也可用NaOH溶液吸收得到Na2CO3溶液,写出该反应的离子方程式          

Na2CO3水溶液呈碱性,其原因是,25℃时该反应的K=2×10-4mol·L-1,则当溶液中c(HCO- 3):c(CO2- 3)=2∶1时,溶液的pH=         

考点:原电池原理电解池原理
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I was telling my boy Sonny the story of the hare and the tortoise. At the end I said, “Son, remember: Be slow and steady, and that will win the race. Don’t you think there’s something to learn from the tortoise?”

Sonny opened his eyes wide, “Do you mean next time when I’m entering for the 60-metre race I should wish that Billy, Tony and Sandy would all fall asleep halfway?”

I was shocked, “But the tortoise didn’t wish that the hare would fall asleep!”

“He must wish that already,” Sonny said, “Otherwise how could he be so foolish as to race with the hare? He knew very well the hare ran a hundred times faster than he himself did.”

“He didn’t have such a wish,” I insisted. “He won the race by pushing on steadily.”

Sonny thought a while. “That’s a lie,” he said. “He won it because he was lucky. If the hare didn’t happen to fall asleep, the tortoise would never win the race. He could be as steady as you like, or a hundred times steadier, but he’d never win the race. That’s for sure.”

I gave up. Today’s children are not like what we used to be. They’re just hopeless.

小题1:The writer argued with his son because ______________.

A.he liked tortoises while his son liked hares

B.they disagreed about whether the tortoise was foolish

C.he tried to teach his son a lesson but the son had totally different opinion

D.he liked the story of the hare and the tortoise while his son didn’t.小题2:Sonny believed that the tortoise ______________.

A.won the race by his own hard working

B.took a risk by agreeing to run a race

C.was not given a fair chance in the race

D.in fact did win the race luckily小题3:Billy, Tony and Sandy must be_______________.

A.boys who were unknown to Sonny’s father

B.boys who Sonny has run races with before

C.boys who Sonny has never raced with before

D.boys who Sonny did not hope to race with again小题4:According to the passage, who do you think learnt a lesson? ______________.

A.The tortoise

B.Sonny

C.The hare

D.Sonny’s father

题型:填空题

位于亚洲西南部,介于伊朗与阿拉伯半岛之间,是往来波斯湾各港的油轮必经之地,素有“海湾咽喉”之称的是( )

A.霍尔木兹海峡
B.马六甲海峡
C.直布罗陀海峡
D.曼德海峡

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如图所示,三个质量完全相同且用同种材料制成的物体,甲为长方体,乙为球体,丙为正方体,放在水平桌面上,它们对桌面的压强大小分别是P、P、P,这三者的大小关系为_____________。

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儿童思想品德的形成是通过教育和自我教育实现的。自我教育能力由______、自我激励和自我调控等因素构成。

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用于涉密网的计算机要专机专用、专人管理,严禁连接其他网络,要阻断和关闭其他网络接口,与公安网和其他网络要做到安全有效的()。

A、适当隔离

B、即时连接

C、物理隔离

D、加密连接

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