2010年10月1日“嫦娥二号卫星”在西昌卫星发射中心点火发射,卫星由地面发射后

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问题:

2010年10月1日“嫦娥二号卫星”在西昌卫星发射中心点火发射,卫星由地面发射后进入地月转移轨道,经多次变轨进入距离月球表面100km,周期为118min的工作轨道,开始对月球进行探测.经过一段时间后,如果卫星的轨道距月球高度逐渐降低,则“嫦娥二号卫星”的(  )

A.线速度逐渐减小

B.角速度逐渐减小

C.周期逐渐减小

D.向心加速度逐渐减小

考点:人造地球卫星万有引力定律的其他应用
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阅读下面短文,根据短文内容及首字母提示补全文中所缺的单词, 答案写在题后的横线上。

“Sorry” is a word that people in Britain often say in their daily life.

One day while I was w   1  on the street, a young man ran by hurriedly, brushing(轻擦)against my handbag. He continued his way, but turned b   2  and said “sorry” to me. Even in a rush, he didn’t f   3   to say “sorry”. One day, after I bought some bananas, the shopkeeper was passing me the change, but I wasn’t ready for it and a coin dropped onto the ground. “Sorry, Madam,” he said w   4   bending to pick it up. I was s   5   why he said “sorry” to me. Another time, I stepped on a man’s f   6  at the entrance to a cinema. At the same time, we b   7  said “sorry”.

Slowly, I got to know that when something unpleasant happens in daily life, the British don’t

c    8   much about who is wrong. If someone is in trouble, a “sorry” is always n   9    .   Perhaps that is w   10   I seldom see people quarrel on the buses or streets in Britain.

小题1: _____________小题2:_____________小题3: _____________ 小题4: _____________小题5: ______________

小题6: _____________ 小题7: _____________ 小题8: _____________ 小题9:_____________ 小题10: _____________

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________生态系统是进行农业生产的场所。

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(12分) 甲醇是一种可再生能源,具有广泛的开发和应用前景。

(1)工业上一般采用下列两种反应合成甲醇:

反应I:  CO(g) + 2H2(g)  CH3OH(g)  ΔH1

反应II: CO2(g) + 3H2(g) CH3OH(g)  +  H2O(g)  ΔH2

①上述反应符合“原子经济”原则的是     (填“I”或“Ⅱ”)。

②已知反应Ⅰ的能量变化如图所示:由表中数据判断  ΔH1      0 (填“>”、“=”或“<”)。

③某温度下,将2 mol CO和6 mol H2充入2L的密闭容器中,充分反应,达到平衡后,测得c(CO)= 0.2 mol/L,    则CO的转化率为          

(2)已知在常温常压下:

① 2CH3OH(l) + 3O2(g) = 2CO2(g) + 4H2O(g)   ΔH =-1275.6 kJ/mol

② 2CO (g)+ O2(g) = 2CO2(g)  ΔH =-566.0 kJ/mol

③ H2O(g) = H2O(l)  ΔH =-44.0 kJ/mol

请计算1 mol甲醇不完全燃烧生成1 mol一氧化碳和液态水放出的热量为________

(3)某实验小组依据甲醇燃烧的反应原理,设计如右图所示的电池装置。

①该电池正极的电极反应为____________

②工作一段时间后,测得溶液的pH减小,该电池总反应的化学方程式为____________.

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錾削硬钢或铸铁时,楔角应取()

A.30°~50°

B.50°~60°

C.60°~70°

D.70°~80°

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现行的《民革章程》是()年通过的。

A、1948

B、2007

C、2012

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