题干

石墨与金刚石都是碳的单质,工业上常用石墨在一定条件下转化为金刚石的反应原理生产人造钻石。已知在100kPa时,12g石墨完全转化成金刚石时需要吸收1.895kJ的能量。则下列说法正确的是 (   )

A:石墨和金刚石互称同位素

B:石墨不如金刚石稳定

C:等质量的石墨和金刚石完全燃烧,放出的能量一样多

D:等质量的石墨和金刚石完全燃烧,金刚石放出的能量多

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D

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    We know that sometimes studying a new language can be hard work but it can be fun too--and if we can make our learning experience fun, then we will learn better. So here are some more of our top tips for making studying fun.

    Firstly,____—make sure your chair is suitable and it's at the right height for the desk. Make sure you have good ventilation(空气流通) and light and the space you're in isn't too hot--you don't want to fall asleep! And put away anything that might distract you, like your smartphone.

    Rather than just staring at books and being passive,____. Why not record yourself and listen back to yourself speaking or reading out information. Or you could turn facts into songs and sing them out loud--this is sure to make information stick in your head!

    ____—lashcards are very useful because they provide visual clues that help you remember things. You could also stick words, grammar rules and other bits of information on notes around your study space or other places around your house--so for example, you can read them when brushing your teeth!

    Don't feel daunted by the amount of studying you have to do.____. Study in small bursts and vary the topics you study so you don't get bored and you stop retaining information. If you can, choose a time of day that best suits your natural preference. Some people work best at night while others work best early in the morning.

    Finally, don't overdo it--know your limits--if you study too hard it won't be fun and you won't absorb information.____—and give yourself a small reward when you do.

A. try to become an active learner

B. So care your mental and physical health

C. get comfortable

D. So take regular breaks

E. Also be creative

F. And don't try to study continuously all day to fit it all in

G. But you can focus on some entertainments