题干

下列各组热化学方程式中,化学反应的△H前者大于后者的是(    )
①C(s)+O2(g)=CO2(g);△H1                       C(s)+1/2O2(g)=CO(g);△H2
②S(s)+O2(g)=SO2(g);△H3                         S(g)+O2(g)=SO2(g);△H4
③H2(g)+1/2O2(g)=H2O(g);△H5                2H2(g)+O2(g)=2H2O(l);△H6
④CaCO3(s)=CaO(s)+CO2(g);△H7              CaO(s)+H2O(l)=Ca(OH)2(s);△H8

A:①

B:④

C:②③④

D:①②③

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C

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Unchangeable Love

    One day I visited an art museum while waiting for my husband to finish a business meeting. I was expecting a quiet 1 of the splendid artwork.

    A young 2 viewing the paintings ahead of me 3 nonstop between themselves. I watched them a moment and decided the lady was doing all the talking. I admired the man's 4 for putting up with her 5 stream of words. 6 by their noise, I moved on.

    I met them several times as I moved 7 the various rooms of art. Each time I heard her continuous flow of words, I moved away 8.

    I was standing at the counter of the museum gift shop making a 9 when the couple approached the 10. Before they left, the man 11 into his pocket and pulled out a white object. He 12 it into a long stick and then tapped his way into the 13 to get his wife's jacket.

     "He's a 14 man." the clerk at the counter said. "Most of us would give up if we were blinded at such a young age. During his recovery, he made a promise his life wouldn't change. So, as before, he and his wife come in 15 there is a new art show."

     "But what does he get out of the art?" I asked. "He can't see."

     "Can't see! You're 16. He sees a lot. More than you and I do," the clerk said. "His wife 17 each painting so he can see it in his head."

    I learned something about patience, 18 and love that day. I saw the patience of a young wife describing paintings to a person without 19 and the courage of a husband who would not 20 blindness to change his life. And I saw the love shared by two people as I watched this couple walk away, hand in hand.