850°C条件下存在可逆反应
，达到最大限度时有90%（体积分数）的氢气转化为水，且知在该状态下存在关系
。则混合气体中二氧化碳和氢气的体积比为（ ）
A．1：1
B．5：1
C．9：1
D．10：1
答案：C
本题考查化学平衡计算；设反应前氢气的体积为1L，则转化的氢气为0.9L，根据平衡状态时的气体的浓度比可知，达到平衡时CO2的体积为8.1L，转化的CO2为0.9L，故原混合气中CO2的体积为9L，V(CO2):V(H2)=9:1。
| 完形填空。 | |||
| Upon receiving the Nobel Peace Prize, Mother Teresa said, "What can you do to 1 world peace? Go home and love your 2 and love your friends. Love them without measure". A 3 story tells of a woman who finally decided to ask her boss for a raise in salary. All day she felt 4 . Late in the afternoon she gathered 5 to see her employer. To her 6 the boss agreed to a raise. The woman 7 her home that evening to a beautiful table set with their best dishes. Her husband had come home early and prepared a festive meal. She 8 if he somehow knew that she would not get 9 . She found him in the kitchen and 10 him the good news. They hugged and kissed, then sat down to the 11 meal. Next to her plate the woman found a beautifully lettered note. It read, " 12 , darling! I knew you'd get the raise! These things will tell you how much I 13 you." Following the supper, her husband went into the kitchen to 14 . She noticed that a second 15 had fallen from his pocket. Picking it off the floor, she read, "Don't worry about not getting the 16 ! You deserve (应得) it anyway! These things will tell you how much I love you." Someone has said that the measure of love is when you love without 17 . What this man feels for his wife is 18 acceptance and love, 19 she succeeds or fails. His love 20 her victories and soothes her wounds. He stands with her, no matter what life throws in their direction. | |||
| ( )1.A. urge ( )2.A. parents ( )3.A. sad ( )4.A. nervous ( )5.A. energy ( )6.A. worry ( )7.A. reached ( )8.A. considered ( )9.A. turned down ( )10.A. declared ( )11.A. optimistic ( )12.A. Good luck ( )13.A. respect ( )14.A. bring up ( )15.A. letter ( )16.A. award ( )17.A. measure ( )18.A. instant ( )19.A. either ( )20.A. celebrates | B. promote B. children B. pleasant B. excited B. strength B. disappointment B. got B. argued B. turned off B. told B. wonderful B. Cheers B. admire B. clean up B. notice B. promotion B. intention B. appropriate B. whether B. admits | C. construct C. wife C. frightening C. desperate C. power C. delight C. arrived C. wondered C. turned over C. informed C. successful C. Congratulations C. envy C. make up C. note C. raise C. discussion C. necessary C. when C. encourages | D. approach D. family D. moving D. dangerous D. courage D. horror D. returned D. thought D. turned out D. proved D. convenient D. Help yourself D. love D. dress up D. poster D. reward D. doubt D. total D. no matter D. believes in |