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问题 单项选择题

计算机的打印设备种类繁多，性能各异，接印字原理分为( )。

A．击打式和非击打式

B．串行打印机和行式打印机

C．宽行打印机和窄行打印机

D．激光印字机和喷墨印字机

答案

参考答案：A

填空题

根据句意和空缺处所给首字母写单词。

1. It is the harvest time. The farmers are b______ getting in the crops.

2. My h____ is collecting stamps. I have collected thousands of stamps.

3. The Chinese people are p____ of the Great Wall. 68._________

4. Mark Twain was born in the USA and English was his mother t______.

5. I'm t________. Could you please bring me a bottle of water.

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选择题

已知：2H2(g)＋O2(g)＝2H2O(l)    ΔH＝－571.6 kJ·mol－1                ①

2CH3OH(l)＋3O2(g)＝2CO2(g)＋4H2O(l)   ΔH＝－1452 kJ·mol－1                ②

H＋(aq)＋OH－(aq)＝H2O(l)    ΔH＝－57.3 kJ·mol－1  下列说法正确的是（  ）

A．H2(g)的燃烧热为571.6 kJ·mol－1

B．同质量的H2(g)和CH3OH(l)完全燃烧，H2(g)放出的热量多

C．H2SO4(aq)＋Ba(OH)2(aq)＝ BaSO4(s)＋H2O(l)　ΔH＝－57.3 kJ·mol－1

D．3H2(g)＋CO2(g)＝ CH3OH(l)＋H2O(l)　ΔH＝＋135.9 kJ·mol－1
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