题干

下列说法正确的是(  )

A:CH4(g)+ 32O2(g)═CO(g)+2H2O(l)△H═﹣a kJ•mol1,这里△H代表燃烧热

B:在25℃、101kPa,1mol硫和2mol硫的燃烧热相等

C:CO是不稳定的氧化物,它能继续和氧气反应生成稳定的CO2,所以CO的燃烧反应一定是吸热反应

D:101kPa时,1mol碳燃烧所放出的热量为碳的燃烧热

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B

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    There exist cruel wars, fighting and sadness in the world today, so it's not only necessary, but also essential to have a good sense of humor just to help us go through difficult times in out lives. Putting a smile on someone's face when you know they are feeling depressed, as the saying goes, makes me feel good and warms my heart.

    How would you feel if you could not joke around with wife, husband, child, co-worker, neighbor, close friend, or even just someone that you are standing in line with at your corner store? I am always saying things that make others smile or laugh, even if I don't know the person I'm joking around with. My Grandma always found humor in everything she did, even if it was the hardest job anyone could imagine. This not only relieves stress in any situation, but also is a common manner to speak to others that are around you.

    I know of a few people that don't have a funny bone in their bodies, as they say. Everyone around them could be rolling on the floor after hearing a great joke and they would sit there without the slightest smile on their faces. They don't get the joke that makes others laugh. I am, busting a gut while they just sit there, looking at me as if I were from outer space. How can people not get a really funny joke?

    Laughing is essential to keep your stress levels under control. Without humor, we would find ourselves with a lot of psychological problems, or on a lot of medications to keep us from going crazy. There is too much sadness and bring a little light into our lives.

    Therefore, I believe our best medicine is to get together and tell some jokes and have some fun laughing together.