题干

使用石油热裂解的副产物CH4来制取CO和H2,其生产流程如图1:

(1)此流程的第Ⅰ步反应为:CH4(g)+H2O(g)⇌CO(g)+3H2(g),一定条件下CH4的平衡转化率与温度、压强的关系如图2.则P1 < P2.(填“<”、“>”或“=”)100℃时,将1mol CH4和2mol H2O通入容积为100L的恒容密闭容器中,达到平衡时CH4的转化率为0.5.此时该反应的平衡常数K=____ 

(2)此流程的第Ⅱ步反应的平衡常数随温度的变化如表:

温度/℃

400

500

830

平衡常数K

10

9

1

从表中可以推断:该反应是____ 反应(填“吸热”或“放热”),若在500℃时进行,设起始时CO和H2O的起始浓度均为0.020mol/L,在该条件下,反应达到平衡时,CO的转化率为____ .如图3表示该反应在t1时刻达到平衡、在t2时刻因改变某个条件引起浓度变化的情况:图中t2时刻发生改变的条件是____ (写出一种).

(3)工业上常利用反应Ⅰ产生的CO和H2合成可再生能源甲醇.

①已知CO(g)、CH3OH(l)的燃烧热分别为283.0kJ•mol﹣1和726.5kJ•mol﹣1,则CH3OH(l)不完全燃烧生成CO(g)和H2O(l)的热化学方程式为____ 

②合成甲醇的方程式为:CO(g)+2H2(g)⇌CH3OH(g)△H<0.在230°C〜270℃最为有利.为研究合成气最合适的起始组成比n(H2):n(CO),分别在230℃、250℃和270℃进行实验,结果如图4所示.其中270℃的实验结果所对应的曲线是____ (填字母);当曲线X、Y、Z对应的投料比达到相同的CO平衡转化率时,对应的反应温度与投较比的关系是____ 

③当投料比为1:1,温度为230℃,平衡混合气体中,CH3OH的物质的量分数为____ (保留1位小数).

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答案(点此获取答案解析)

2.25\u00d710\ufe634,\u653e\u70ed,75%,\u964d\u4f4e\u6e29\u5ea6\uff0c\u6216\u589e\u52a0\u6c34\u84b8\u6c7d\u7684\u91cf\uff0c\u6216\u51cf\u5c11\u6c22\u6c14\u7684\u91cf,CH3OH\uff08l\uff09+O2\uff08g\uff09=CO\uff08g\

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    As a young boy, I sometimes traveled the country roads with my dad. He was a rural mill carrier, and on Saturdays he would ask me to go with him. Driving through the countryside was always an adventure: There were animals to see, people to visit, and chocolate cookies if you knew where to stop, and Dad did.

    In the spring, Dad delivered boxes full of baby chickens, and when 1 was a boy it was such a fun to stick your finger 'through one of the holes of the boxes and let the baby birds peck on your fingers.

    On Dad' s final day of work, it took him well into the evening to complete his rounds because at least one member from each family was waiting at their mailbox to thank him for his friendship and his years of service. "Two hundred and nineteen mailboxes on my route." he used to say, "and a story at every one. " One lady had no mailbox, so Dad took the mail in to her every day because she was nearly blind. Once inside, he read her mail and helped her pay her bills.

Mailboxes were sometimes used for things other than mail. One note left in a mailbox read. "Nat, take these eggs to Marian; she's baking a cake and doesn't have any eggs. " Mailboxes might be buried in the snow, or broken, or lying on the groom:. bat the mail was always delivered On cold days Dad might find one of his customers waiting for him with a cup of hot chocolate. A young wrote letters but had no stamps, so she left a few button on the envelope in the mailbox; Dad paid for the stamps. One businessman used to leave large amounts of cash in his mailbox for Dad to take to the bank. Once, the amount came to 8 32,000.

    A dozen years ago, when I traveled back to my hometown on the sad occasion of Dad's death,  the mailboxes along the way reminded me of some of his stories. I thought I knew them all, but that wasn't the case.

    As I drove home, I noticed two lamp poles, one on each side of the street. When my dad was around, those poles supported wooden boxes about four feet off the ground. One box was painted green and the other was red, and each had a long narrow hole at the top with white lettering: SANTA CLAUS, NORTH POLE. For years children had dropped letters to Santa through those holes.

    I made a turn at the comer and drove past the post office and across the railroad tracks to our house. Mom and I were sitting at the kitchen table when I heard footsteps. There, at the door, stood Frank Townsend, Dad's postmaster and great friend for many years. So we all sat down at the table and began to tell stories.

    At one point Frank looked at me with tears in his eyes. " What are we going to do about the letters this Christmas?" he asked.

    "The letters?"

    'I guess you never knew. "

    "Knew what?"

    " Remember, when you were a kid and you used to put your letters to Santa in those green and red boxes on Main Street? It was your dad who answered all those letters every year. "

    I just sat there with tears in my eyes. It wasn't hard for me to imagine Dad sitting at the old table in our basement reading those letters and answering each one. I have since spoken with several of the people who received Christmas letters during their childhood, and they told me how amazed they were that Santa had known so much about their homes and families.

For me, just knowing that story about my father was the gift of a lifetime.