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问题 不定项选择题

已知热化学方程式：

①CO(g)+1/2O2(g)=CO2(g) △H= -283.0kJ/mol

②H2(g)+1/2O2(g)=H2O(g) △H=-241.8kJ/mol

则下列说法正确的是

[ ]

A．H2的燃烧热为241. 8kJ/mol

B．由反应①、②可知如图所示的热化学方程式为CO(g)+H2O(g)=CO2(g)+H2(g) △H=-41. 2kJ/mol

C．H2(g)转变成H2O(g)的化学反应一定要释放能量

D．根据②推知反应H2(g)+1/2O2(g)=H2O(l) △H>-241. 8kJ/mol

答案

答案：B

单项选择题

How should one invest a sum of money in these days of inflation (通货膨胀) Left in a bank it will hardly keep its value, however high the interest rate is. Only a brave man, or a very rich one, dares to buy and sell on the Stock Market. Today it seems that one of the best ways to protect your savings, and even increase your wealth is to buy beautiful objects from the past. Here I am going to offer some advice on collecting antique clocks, which I personally consider are among the most interesting of antiques.
I sometimes wonder what a being from another planet might report back about our way of life. "The planet Earth is ruled by a mysterious creature that sits or stands in a room and makes a strange ticking sound. It has a face with twelve black marks and two hands. Men can do nothing without its permission, and it fastens its young round people’s wrists so that everywhere men go they are still under its control. This creature is the real master of Earth and men are its slaves. "
Whether or not we are slaves of time today depends on our culture and personality, but it is believed that many years ago kings kept special slaves to tell the time. Certain men were very clever at measuring the time of day according to the beating of their own hearts. They were made to stand in a fixed place and every hour or so would shout the time. So it seems that the first clocks were human beings.
However, men quickly found more convenient and reliable ways of telling .the time. They learned to use the shadows cast by the sun. They marked the hours on candles, used sand in hour-glasses, and invented water-clocks. Indeed, any serious student of antiques should spend as much time as possible visiting palaces, stately homes and museums to see some of the finest examples of clocks from the past.
Antique clocks could be very expensive, but one of the joys of collecting clocks is that it is still possible to find quite cheap ones for your own home. After all, if you are going to be ruled by the time, why not invest in air antique clock and perhaps make a future profit

By quoting (引用) the remark of a being from another planet, the author intends to ______.

A．suggest human beings are controlled by a clock

B．describe why clocks can rule the planet Earth

C．tell readers what clocks look like

D．compare clicks to human beings
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单项选择题

精神分析学派理论着眼于游戏与儿童的( )的发展。

A．人格和情绪
B．气质和兴趣
C．行为和动力
D．个体认知
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