零件加工表面上因具有这种较小间距和峰谷而形成的微观（）误差，

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问题单项选择题

零件加工表面上因具有这种较小间距和峰谷而形成的微观（）误差，称为表面粗糙度。

A.多维

B.平面

C.几何形状

D.立体形状

答案

参考答案：C

阅读理解

Spaceship	Time	Astronaut	Event
Shenzhou V	2003.10.15 —10.16	Yang Liwei	China became the third country to succeed in sending up the manned spaceship into space.
Shenzhou VI	2005.10.12 —10.17	Fei Junlong Nie Haisheng
Shenzhou VII	2008.9.25 —9.28	Zhai Zhigang Liu Boming Jing Haipeng	Three Chinese astronauts were sent into the space together. Zhai Zhigang went out of the spaceship and walked in space for the first time.
Shenzhou VIII	2011.11.1 —11.17	No astronaut	Shenzhou VIII connected itself to Tiangong I successfully.
Shenzhou IX	2012.6.16 —6.29	Jing Haipeng Liu Wang Liu Yang	Astronauts connected Shenzhou IX to Tiangong I successfully by controlling them by hand. Liu Yang became the first woman astronaut who came into the space in China.

根据表格内容，选择最佳答案。
小题1:______ country (countries) had sent their astronauts into space before China.

小题2:______ was sent into the space twice among these astronauts.

小题3:______ walked in the space for the first time in China.

小题4:_______ has the same number of astronauts as Shenzhou IX.

小题5:Liu Yang ________ in China.

A．became the first woman astronaut who came into the space

B．is the first astronaut who came into the space

C．walked in the space for the first time

D．connected Shenzhou VIII to Tiangong I successfully

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填空题

每空2分，共12分）化学反应可为人类提供能量

（Ⅰ）家用液化气的主要成分之一是丁烷（C₄H₁₀），常温常压下，当5.8 kg丁烷完全燃烧并生成二氧化碳和液态水时，放出热量为2.9×10⁵kJ，试写出丁烷燃烧的热化学方程式：____________________________________________，已知1mol液态水气化时需要吸收44 kJ的热量，则反应：

的ΔH为____________________。

（Ⅱ）铅蓄电池是化学电源，其电极材料分别是Pb和PbO₂，电解质溶液为稀硫酸。工作时，该电池的总反应为PbO₂+Pb+2H₂SO₄=2PbSO₄+2H₂O，根据上述情况判断：

（1）蓄电池的负极是______，其电极反应式为______________________________。

（2）蓄电池的正极电极反应式为_________________________________。

（3）蓄电池工作时，其中电解质溶液的pH______（填“增大”、“减小”或“不变”）。

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