试题与答案

在化学反应中,反应物转化成生成物,必然发生能量的变化。 (1)下列说法正确的是。

题型:填空题

题目:

在化学反应中,反应物转化成生成物,必然发生能量的变化。

(1)下列说法正确的是       

A.化学变化中的能量变化主要由化学键变化引起的

B.放热反应发生时不一定要加热,但吸热反应必须要加热才能发生

C.钢铁的吸氧腐蚀和析氢腐蚀的负极反应都为Fe—2e= Fe2+

D.CaCO3(s) =" CaO(s)" + CO2(g) ΔH=" +" 178.5 KJ·mol-1的意义是表示1mol CaCO3完全分解生成1mol CaO和1mol CO2气体要放出178.5 KJ的热量(2)101 kPa条件下,氮气和氢气反应生成氨气的能量变化示意图如下:

已知:①a=1127;②b=1219

则:1molN2和3molH2参与反应生成2molNH3        (填“吸收”或“放出”)热量         KJ。

答案:

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Forty-five years ago, Martin Luther King had a dream of an America where men and women would be judged not by the colour of their skin but by the content of their character. Today the dream has come true.

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B.Before November 4

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A.His grandmother passed away.

B.His grandmother was killed.

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D.His grandmother was kidnapped.小题3:What does the underlined word “campaign” mean in Chinese?

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D.比赛小题4:Which of the following is NOT true?

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C.Obama’s grandmother had a great effect on him.

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