5.下列原子結(jié)構(gòu)示意圖中，表示帶兩個(gè)單位正電荷的離子的是

A.　　　　　　　 　　　B.　　　　　　　　　 　C.　 　　　　　　　　D.

4.下列關(guān)于燃燒現(xiàn)象的描述中正確的是

　A.木炭在空氣中燃燒后，生成黑色的固體　　　 B.硫粉在氧氣中燃燒，產(chǎn)生大量白煙

　C.鎂條在空氣中燃燒，發(fā)出耀眼的白光 　　　　D.紅磷在空氣中燃燒，產(chǎn)生藍(lán)紫色火焰

3.盛放酒精的試劑瓶的標(biāo)簽上應(yīng)印有下列警示標(biāo)記中的

2.石油沒有固定的沸點(diǎn)，煉油廠根據(jù)石油中各成分沸點(diǎn)不同，將其分離開來，得到汽油、 煤油、柴油等。由此推斷石油屬于

A.單質(zhì)　　　　　　 B.混合物　　 C.純凈物　　　　 D.化合物

1.下列現(xiàn)象中發(fā)生化學(xué)變化的是

A.紙張燃燒　 B.玻璃破碎　 C.冰雪融化　 D.酒精揮發(fā)

1. --This green coat looks nice on you and it is only 200 Yuan. --OK.______. A. I'll need it　 B . I'll take it　C. It's much too expensive.　 D. I'd like to sell it.　 2.　He left ______any of his friends _____ him _____. A. with; seeing; off　B. without; seeing; off　C. without; see; /　D. with; see; out 3.　______ is _____ the students to find out the meaning and the usage of new words. A. What a dictionary does; help　　B. What dictionary does; to help C. How a dictionary does; help　　D. All that a dictionary does; helps　 4.　The landowners in India would not vote to lose their land and wealth, _____ it resulted ______ a fairer society. A. even if; in　B. even though; of　C. as if; in　D. whether; of 5.　Towards _____ evening, _____ heavy rain began to fall. A. the; a　B. /; a　C. /; the　D. the; /　 6.　--Do you have _____ more to get in the market? --No, only some bread and butter. A. something　B. everything　C. nothing　D. anything 7.　The teacher as well as her students _____ to visit the Moter Company tomorrow. A. go　B. are to go　C. is to go　D. is about to go.　 8.　The building is _____. A. twenty-metre-high　　B. twenty metre high C. twenty-metres-high　　D. twenty metres high　 9.　The book ____ three Yuan, but it only ____ me two Yuan. A. spends, take　B. costs, spend　C. costs, cost　D. pays, cost　 10.　They are____ the same size. You can take ______ half of the bread. A. in, either　B. with, either　C. in, both　D. at, none　 11.　--Hello. May I speak to Mr. Wang, please?　　　　 -- _______. A. Hold the line. please　B. Wait for a minute　C. Here it is　D. Here he is　 12.　You can choose _____ book you like among these. A. no matter what　B. whatever　C. whose　D. whichever　 13.　This kind of paper was as soft and light as silk but ______ expensive. A. much less　B. much little　　　 C. many less　D. much more than　 14.　It had rained for several days. The clothes had _____ near the fire to dry. A. hang up　B. to hung up　C. to be hung up　D. to be hanged up　 15.　The line is engaged. I can't _____ now. A. get on　B. get along　　　 C. get through 　D. get down　 16. We should prevent pollution ________ happily. A. to live　　B. for living　　C. from living　D. living　 17. As we all know, ______ knowledge comes from _______ practice. A. the; the　B. a; a　　C. the ;×　D. ×; × 18. Sports build the body _______ reading builds the mind. A. while　　B. when　　C. as　　D. for 19. The mother ________ her son's success in the newspaper. A. learned about　B. learned　　C. heard　　D. learned from 20. "Don't forget to come to my birthday party tomorrow." "__________." A. I don’t'　B. I won't　　C. I can't　　D. I haven't　 21. She was given the chance to ______ designing the new bridge. A. take part in　B. attend　C. go all out　D. join 22. Don't read ______ books ________ you can not understand. A. same…as　B. the same …like　C. such …as　D such… like 23. Bob: How long have you lived here?　　Sue: _________. A. Since the beginning of the year.　　B. In 1990 C. Not long ago　　　 　　　 D. Only until the end of the year　 24. Do you mind _______ alone at home? 　 A. Jack's being left　B. Jack leaving　C. Jack having left　D. Jack to be left　 25. Mary realized she ______. A. was playing a joke about　　B. was making fun C. was being made fun of　　　D. was made fun　 26. Peter: Do you want a ride? Dick: _______ Peter: I asked if you wanted a ride? A. I don't mind.　　　B. I beg your pardon? C. I'll take a taxi.　　　D. I don’t' want a ride.　 27. _______ the manager? A. Who is in place of　　　B. Who is in the place of C. Who shall take the place of　　D. Who will take place of　 28. Mary: What do you think of my new dress? Sue: ________. A. It is on sale　　　B. You really have a new dress C. It looks very good on you　　D. I think it's a birthday present for you 29. Patty: How about going for a walk? Nancy: ________. A. I'll walk with you at eight　　B. That's not a bad idea C. Walking is a kind of exercise　　D. It will take me minutes to have a walk　 30. I found him _________ in an armchair, ___________. A. sit…and read　B. seated…reading　C. sitting…and read　 D. seating…reading 31. If you don't turn up by 8 o'clock, we'll go ______ you. A. without　B. except　　C. but　　D. besides 32. --Has Jane arrived yet?　　　　 --No, she_______ an hour ago. A. was supposed to come　　B. must have come C. should come　　　D. ought to have come　 33. _______ in time, little Franz was afraid. ________ scolded. A. Not having come…of being　　B. Having not come…to be C. Having not come…of being　　D. Not having come…to be 34. No one but Rose and Kate _______ a fine red coat. A. put on　　B. is wearing　C. dresses　D. have on　 35. The battle lasted for a few hours and at last the enemy ________. A. was defeated　B. were beat　C. were won　D. defeated　 36. He is not a man easy ______. A. to deal　　B. to deal him　C. to deal with　D. to deal with him 37. Mr. Li is gaining _______. He has to do some exercises to lose _______.　 A. weighty…weigh　B. weight…weight　C. fat…weigh　D. weighty…h(huán)eavy 38. The clock ________ and we realized it was five o'clock. A. hit　　B. beat　　C. struck　　D. run　 39. Reading without stop is a ______ piece of work. A. tire　　B. tired　　C. tiresome　D. troubled　 40. He was afraid there was any wild animal around him, looking round from ________. A. time to a time　B. time to time　C. a time to a time　D. times to times　 41. It ________ that there is no way out of difficulty. A. looks　　B. thinks　　C. believes　D. seems 42. We were told that it was our _______ to read the text together. A. action　　B. turn　　C. absence　D. sign 43. --Why doesn't he buy you a drink? --I don't know why, but it isn't _______ he had no money. A. even if　　B. as if　　C. that　　D. because 44. What way are you thinking of _______ rid of this kind of pollution? A. to get　　B. get　　C. getting　　D. got 45. The angry boss ________ from the chair and went directly to him. A. lifted　　B. raised　　C. rose　　D. carried　　 46. The schoolboy regretted _______ after he didn't pass his exam. A. the time on TV　　　B. to spend so much time on TV C. taking most of his time on TV　D. spending so much time on TV　 47. Have you found his name ______ in the papers? A. signing　B. signed　　C. to sign　　D. sign　　 48. Since we have met again after all these years, let's ________ each other from now on. A. keep up with　B. keep out of　C. keep in touch with　D. keep touching　 49. The ______ in the mountain village struck most of the visitors. A. scenes　　B. space　　C. absence　　D. flight　　 50. It is difficult for you to ______ what will happen in space without gravity. A. depend on　B. have some idea of　C. keep from　　D. equip with　 51. The two brothers carried a ______ bed into the room. A. double　　B. deal　　C. slight　　D. opposite　 52. The accident ______ for a new car. Because the old one was destroyed. A. sent me looking　B. made preparations　C. kept me from looking　D. was fit　 53. --How is it that you are late for class again?　　　　　　 --________. A. By bus and then on foot　　B. It's quite all right C. Because I missed the bus　　D. It's far from school　　　 54. Hearing the sound of shots, the birds flew away ______ all directions. A. at　　B. for　　C. from　　D. in　 55. _______ the normal condition, he can read 150 words a minute. A. Below　　B. Under　　C. With　　D. In　　 56. Tom is good boy and _______ he is honest. He never tells a lie. A. at all　　B. in all　　　 C. above all　　D. after all　　 57. Many facts proved that long before Columbus ________ America, Chinese had visited it. A. noticed　B. uncovered　　　 C. discovered　D. arrived　　 58. The meeting was _______. Many people were for our plan. A. a success　B. success　　　 C. succeed　　D. failure　 59. --How much is it ______?　　　　　　 --$ 20, I think. A. spent　　B. cost　　　 C. worth　　D. taken　 60. The world is _______ seven continents and four oceans. 　 A. made up of　B. made out of　C. made from　D. made in　 61. --Can I help you? --I'd like to have my package ______, madam. A. be weighed　B. to be weighed　　 C. to weigh　　D. weighed　 62. I'm so busy that I can't ______ the time for a holiday at present. A. spare　　B. share　　　 C. spend　　D. take　 63. They would _______ for Guangzhou the next morning and so they went to bed early. A. set out　B. set about　　　 C. set up　　D. set to　 64. He insisted on his ______ Dr Turner instead of Mr. Turner. A. called　　B. calling　　　 C. being called　D. been called 65. John: _________ Jack: In two weeks. John: Are you going to Japan? Jack: No. I'm going to Australia. I went to Japan two years ago. A. How long have you been here?　　B. When is your holiday? C. When are you leaving for Australia?　D. How long do you plan to stay here? 66. Mary ________ passing the entrance examination. A. succeeded　　　B. succeeded in C. succeeds in　　　D. succeeds　 67. Tell the child not to drink _______ water. A. boiled　　B. boil　　C. boiling　　D. boils　 68. i set _________ tomorrow on my journey to America. A. on　　B. up　　C. to　　　D. out 69. The shop owner would _______ his money every day. A. count　　B. count for　C. count out　　D. counting　 70. The old lady devoted her lifetime _______ the homeless children. A. to help　　B. to helping　C. helping　　D. for help　 71. Tom: Would you like me to water your plants while you're on your holiday? Joe: ________ A. No problem. I was more than glad to do it. B. I appreciate it, but I'm already finished watering them. C. Thanks for offering your help, but my brother's going to do it. D. Certainly watering plants is my favorite pastime.　 72. --Don't you think it's going to rain over the weekend? --_______. A. I don't believe　B. I don't believe it　C. I believe not so　D. I believe not　 73. I knew I should not accept anything from such a person but I found it difficult to turn down his ___. A. plan 　　B. offer　　C. suggestion　D. request 74. --Do you mind my taking this seat?　　　　 --________. A. Yes, sit down please　　B. No, of course not C. Yes, take it please　　D. No, you can't take it　 75. How I envy you _______ your good luck!　 A. in　　B. of　　C. to　　D. /　　 76. This event was rather unusual, ________? A. is it　　B. isn't it　　C. was it　　D. wasn't it　 77. We have _______ books in our library. A. plenty of　B. great many　C. a great deal of　D. great number of 78. The police saw the woman _______ a bus and _______ a taxi. A. get off …get on　　B. get on … get off C. get off …get into　　D. get on … get into　 79. Do you mind ______ how you succeed? A. if I go and see　B. if I go seeing　C. my going and see　D. my go to see 80. The boy would have died, _______ on him without delay. A. if the doctor didn't operate　B. if the doctor wouldn't operate C. would the doctor not operate　D. had the doctor not operated 81. Only when ______ in 1918, ______ happily back to work. A. the war was over … he went　B. was the war over … did he go C. the war was over … did he go　D. was the war over … he went　　 82. --Who telephoned just now? --Sorry. I couldn't ______ the voice. A. recognize　B. realize　C. know　　D. understand　　 83. He had ______ in finding Mr. Green's house. A. many difficulties　　B. many difficulty C. much difficulties　　D. much difficulty 84. I don't want to _______ money on such books. A. cost　　B. pay　　C. spend　　D. take 85. --Thank you for your help.　　　　　 --________. A. All right　B. That's right　C. You're right　D. That's OK　 86. The man is standing _______ his back _______ the fire. A. with … to　B. with … against　C. on …for　D. at … of 87. I looked everywhere in the house ______ a key that had been lost. A. in searching for　　B. in search of C. to search　　　D. searching of 88. I insisted that he_______ at once. A. leave　　B. left　　C. leaves　　D. leaving　 89. When will you _______ me the money that was borrowed? A. pay　　B. repay　　C. pay for　　D. repay for　 90. "Do you have any clothes to ______, Tom?" mother asked. A. wash　　B. washing　C. be washed　D. washed　 91. You may use the book as you like, _______ you keep it clean. A. unless　　B. so long 　C. as long　　D. so long as　 92. He ________ the world record. A. failed to break　B. failed to breaking　C. failed breaking　D. failed broken 93. No ________ what you say, _______exists in three states. A. matter…matters　　　B. matter…matter C. matters…matter　　　D. matters…matters　　 94. I wonder what time lunch is_______ in your school. A. given　　B. taken　　C. served　　D. eaten　　 95. The people in some countries ________ freedom. A. longed　B. long for　C. longing　　D. longing for　 96. I ______ all the bookshops in our town for the book I needed but I couldn't get one. A. hunted　B. found　　C. looked for　　D. searched for　 97. A piece of ______ music will make you happy. A. fond　　B. pleased　C. merry　　D. glad 98. --You seem to get lost. Need help? -- _______ A. Yes, would you please help me with the bag? B. Help me find my key, please. C. Yes, give me a hand, please. D. I'm looking for Zhongshan Road.　 99. --I must apologize for _______ ahead of time. --That's all right. A. letting you not know　　B. not letting you know. C. letting you know not　　D. letting not you know　 100. The students are well _______ the exam. They are sure to get good marks. A. prepared for　B. ready for　　C. prepared　　D. preparing　 101. Yesterday the president spoke on TV to the _______. A. country　B. nation　　C. land　　D. state　 102. The nurse gave ________ the sweets to the children. A. up　　B. off　　C. out　　D. in 103. Remember to______ a stamp on the envelope before you post it. A. put　　B. place　　C. strike　　D. stick　 104 John: Do you happen to have twenty dollars with you? Jack: _______ John: I want to buy a notebook. A. How do you want it?　B. How much? C. What for?　　　D. When can you pay me back?　 105. After school was over the boys ________ their books and went home. A. put in　　B. put aside　　C. put away　　D. put up 106. _______ went to see the film yesterday. A. Every of them　　　B. Both they C. Nobody of them　　　D. Not all of them　　 107. The higher the birds flew, _______ we could see them. A. less clearly　　　B. the less clearly C. more clear　　　D. more clearly　　 108. With her long beautiful hair gone _______ would be no use for the combs. A. she　　B. they　　C. there 　　D. it.　 109. Joe: Why don't you tell me a few things about your country? Ken: __________ A. Because I can't tell you many things at a time　B. I'm afraid I can't. C. Sure. What in general are you interested in?　D. I don’t know anything about that.　 110. --You look so worn-out! --i lay ________ all the night. A. woke　　B. awake　　C. slept　　D. asleep 111. When you ______ the book please return it to the library on time. A. get through　B. get along　　　 C. look through　D. look up 112. Both the man and his horse ________ after the long ride. A. gave out　B. worn out　　C. tired out　D. run out　 113. You _______ last night, but you went to the concert. A. must have studied　　　B. might study C. should have studied　　D. would study　　 114. Teacher: You can't finish the book in less than an hour, I suppose? Student: __________. A. Yes, I'm sure I can　　　B. No, hardly C. Sorry, I can't　　　D. I don't think I can　　 115. Tom: My brother will be surprised when he opens this package I'm sending. Jack: Why are you sending him a package? Tom: __________. A. It's a new radio　　　B. It's his birthday C. It's very expensive　　　D. It's too late 116. "Have a nice weekend!" " _________." A. The same to you　　　B. You do too C. The same as you　　　D. You have it too　 117. Joe: Are you taking some gifts with you when you return to America? Dan: I'm planning to do so. Have you any suggestions? Joe: __________. A. I'm leaving tomorrow　　　B. I'm taking a plane C. Why don't you buy some bamboo works?　D. I posted them to America yesterday 118. ―What happened to the old mail carrier? ―He _______ to a new neighborhood to work. A. has sent 　B. has been sent 　C. was sent 　D. sent 119. Mary: This handbag isn't yours, is it? Joan: __________. A. Yes, it's not mine　　B. No, yours is bigger C. Yes, it's my friend's　　D. No, mine is a red one　 120. "Hi, haven't seen you for ages! You look fine!" "__________. You look well, too." A. Great　　B. Thanks　　C. Oh, no　　D. Not at all　

40．(09年山東理綜·28)(14分)運(yùn)用化學(xué)反應(yīng)原理研究氮、氧等單質(zhì)及其化合物的反應(yīng)有重要意義。

(1)合成氨反應(yīng)N₂(g)+3H₂(g)2NH₃(g)，若在恒溫、恒壓條件下向平衡體系中通入氬氣，平衡　　　 移動(填“向左”、“向右”或“不”)；使用催化劑　　　　 反應(yīng)的△H(填“增大”、“減小”或“不改變”)。

(2)已知：O₂(g) = O₂⁺(g)+e^－　　　　　　 H₁=1175.7 kJ·mol^-1

PtF₆(g)+e^－=PtF₆^－(g)　　　　　　　　　　 H₂=-771.1 kJ·mol^-1

O₂PtF₆(S)=O₂⁺(g)+PtF₆^－(g)　　　　　　　 H₃=482.2 kJ·mol^-1

則反應(yīng)O₂(g)+PtF₆(g) = O₂⁺PtF₆^－(s)的H=_____________ kJ·mol^-1。

(3)在25℃下，向濃度均為0.1 mol·L^-1的MgCl₂和CuCl₂混合溶液中逐滴加入氨水，先生成　　　　 沉淀(填化學(xué)式)，生成該沉淀的離子方程式為　　　　 。已知25℃時(shí)K_sp[Mg(OH)₂]=1.8×10^-11，K_sP[Cu(OH)₂]=2.2×10^-20。

(4)在25℃下，將a mol·L^-1的氨水與0.01 mol·L^-1的鹽酸等體積混合，反應(yīng)時(shí)溶液中c(NH₄^*)=c(Cl^-)。則溶液顯　　　 性(填“酸”、“堿”或“中”)；用含a的代數(shù)式表示NH₃·H₂O的電離常數(shù)K_b=　　　　　　 。

答案：(1)向左 不改變

(2)－77.6

(3)Cu(OH)₂　 Cu²⁺+2NH₃·H₂O = Cu(OH)₂↓ +2NH₄⁺

　　　　 (4)中　　 　mol·L^-1

解析：(1)恒溫、恒壓條件下向平恒體系中通入氬氣，則反應(yīng)體系體積增大，平衡左移；使用催化劑只是改變了反應(yīng)的途徑，沒有改變反應(yīng)物與生成物的狀態(tài)，△H不變；(2)利用蓋斯定律，△H₁+△H₂+(-△H₃)= -77.6 kJ·mol^-1；(3)由于,K_sP [Cu(OH)₂]=2.2×10^-20＜K_sp[Mg(OH)₂]=1.8×10^-11，所以先生成沉淀；2NH₃·H₂O+Cu²⁺＝Cu(OH)₂↓+2 NH₄^*；根據(jù)溶液的電中性原則，c(NH₄^*)=c(Cl^-)，則[H⁺]＝[OH^-]；溶液顯中性；K_b= ，c(NH₄^*)=c(Cl^-)＝0.005 mol·L^-1；[H⁺]＝[OH^-]＝1×10^-7 mol·L^-1(因?yàn)槭?5℃下且為中性)；[NH₃·H₂O]＝mol·L^-1－0.005 mol·L^-1，則：K_b=mol·L^-1。

39．(09年寧夏理綜·28)(14分)2SO₂(g)+O₂(g) 2SO₃(g)反應(yīng)過程的能量變化如圖所示。已知1mol SO₂(g)氧化為1mol SO₃的ΔH=-99kJ·mol^-1.請回答下列問題：

(1)圖中A、C分別表示　　 、　　 ，E的大小對該反應(yīng)的反應(yīng)熱有無影響？　 。該反應(yīng)通常用V₂O₅作催化劑，加V₂O₅會使圖中B點(diǎn)升高還是降低？　 ，理由是　　　 ；

(2)圖中△H=　 kJ·mol^-1；

(3)V₂O₅的催化循環(huán)機(jī)理可能為：V₂O₅氧化SO₂時(shí)，自身被還原為四價(jià)釩化合物；四價(jià)釩化合物再被氧氣氧化。寫出該催化循環(huán)機(jī)理的化學(xué)方程式　　　　　 ；

(4)如果反應(yīng)速率v(SO₂)為0.05 mol·L^-1·min^-1，則v(O₂)=　　　 mol·L^-1·min^-1、v(SO₃)=　　　 mol·L^-1·min^-1；

(5)已知單質(zhì)硫的燃燒熱為296 KJ·mol^-1，計(jì)算由S(s)生成3 molSO₃(g)的△H　　　

　(要求計(jì)算過程)。

答案：(1)反應(yīng)物能量　 生成物能量　 (2)無　 降低　 因?yàn)榇呋瘎└淖兞朔磻?yīng)的歷程使活化能E降低　 (3)-198　 (4)SO₂ +V₂O₅=SO₃+2VO₂　 4VO₂+ O₂=2V₂O₅　 (4)0.025　 0.05

(5)S(s)+O₂(g) =2SO₂(g)△H₁=-296 KJ·mol^-1 ， SO₂(g)+1/2O₂(g) SO₃(g) △H₂=-99 KJ·mol^-1　

3S(s)+9/2O₂(g)=3SO₃(g) △H=3(△H₁+△H₂)=-1185 KJ·mol^-1　

解析：(1)本小題考查反應(yīng)物總能量高于生成物總能量為放熱反應(yīng)，可得到A和C所表示的意義，E為活化能與反應(yīng)熱無關(guān)，但是用催化劑可以降低活化能；(2)圖中表示的是2molSO₂的反應(yīng)，因此△H=-99×2KJ·mol^-1；(3)依題意即可寫出：SO₂ +V₂O₅=SO₃+2VO₂　 4VO₂+ O₂=2V₂O₅；(4)依據(jù)速率之比等于化學(xué)計(jì)量數(shù)之比

38．(09年江蘇化學(xué)·20)(10分)聯(lián)氨(N₂H₄)及其衍生物是一類重要的火箭燃料。N₂H₄與N₂O₄反應(yīng)能放出大量的熱。

(1)已知：2NO₂(g)===N₂O₄(g)　 △H=-57.20kJ·mol^-1。一定溫度下，在密閉容器中反應(yīng)2NO₂(g)N₂O₄(g)達(dá)到平衡。其他條件不變時(shí)，下列措施能提高NO₂轉(zhuǎn)化率的是　　 (填字母)。

A．減小NO₂的濃度　　　　　　　　　　　　　　　　 B．降低溫度

C．增加NO₂的濃度　　　　　　　　　　　　　　　　 D．升高溫度

(2)25℃時(shí)，1.00gN₂H₄(l)與足量N₂O₄(l)完全反應(yīng)生成N₂(g)和H₂O(l)，放出19.14kJ的熱量。則反應(yīng)2N₂H₄(l)+N₂O₄(l)=3N₂(g)+4H₂O(l)的△H=　　　 kJ·mol^-1。

(3)17℃、1.01×10⁵Pa，密閉容器中N₂O₄和NO₂的混合氣體達(dá)到平衡時(shí)，c(NO₂)=0.0300 mol·L^-1、c(N₂O₄)=0.0120 mol·L^-1。計(jì)算反應(yīng)2NO₂(g)N₂O₄(g)的平衡常數(shù)K。

(4)現(xiàn)用一定量的Cu與足量的濃HNO₃反應(yīng)，制得1.00L已達(dá)到平衡的N₂H₄和NO₂的混合氣體(17℃、1.01×10⁵Pa)，理論上至少需消耗Cu多少克？

答案：(1)BC

(2)-1224.96

(3)根據(jù)題意知平衡時(shí)：c(N₂O₄)=0.0120 mol·L^-1、c(NO₂)=0.0300 mol·L^-1

K==13.3L·mol^-1

答：平衡常數(shù)為13.3。

(4)由(3)可知，在17℃、1.01×10⁵Pa達(dá)到平衡時(shí)，1.00L混合氣體中：

n(N₂O₄)=　c(N₂O₄)×V=0.0120 mol·L^-1×1.00L=0.0120mol

n(NO₂)=　c(NO₂)×V=0.0300 mol·L^-1×1.00L=0.0300mol

則 n (NO₂) 總= n(NO₂)+2n(N₂O₄)=0.0540mol

由Cu+4HNO₃=Cu(NO₃)₂+2NO↑+2H₂O可得

答：理論上至少需消耗Cu 1.73 g.

解析：(1)考查影響化學(xué)平衡移動的因素(2)簡單的反應(yīng)熱計(jì)算要注意將質(zhì)量轉(zhuǎn)化為物質(zhì)的量，還要注意比例關(guān)系。(3)(4)見答案

[考點(diǎn)分析]^{本題考察了平衡移動原理、反應(yīng)熱計(jì)算、平衡常數(shù)。高考中的熱點(diǎn)和難點(diǎn)。}

37．(09年廣東化學(xué)·20)(10分)

　甲酸甲酯水解反應(yīng)方程式為：

HCOOCH₃(l)+H₂O(l)HCOOH(l)+CH₃OH(l)；△H>0

某小組通過試驗(yàn)研究該反應(yīng)(反應(yīng)過程中體積變化忽略不計(jì))。反應(yīng)體系中各組分的起始量如下表：

甲酸甲酯轉(zhuǎn)化率在溫度T₁下隨反應(yīng)時(shí)間(t)的變化如下圖：

(1)根據(jù)上述條件，計(jì)算不同時(shí)間范圍內(nèi)甲酸甲酯的平均反應(yīng)速率，結(jié)果見下表：

請計(jì)算15-20min范圍內(nèi)甲酸甲酯的減少量為　　　　　 mol，甲酸甲酯的平均反應(yīng)速率為 　　　mol·min^-1(不要求寫出計(jì)算過程)。

(2)依據(jù)以上數(shù)據(jù)，寫出該反應(yīng)的反應(yīng)速率在不同階段的變化規(guī)律及其原因：　　　　 　。

(3)上述反應(yīng)的平衡常數(shù)表達(dá)式為：，則該反應(yīng)在溫度T₁下的K值為 　　　　　　　。

(4)其他條件不變，僅改變溫度為T₂(T₂大于T₁)，在答題卡框圖中畫出溫度T₂下甲酸甲酯轉(zhuǎn)化率隨反應(yīng)時(shí)間變化的預(yù)期結(jié)果示意圖。

答案：(1)15-20min范圍內(nèi)甲酸甲酯的減少量為0.045mol；甲酸甲酯的平均反應(yīng)速率為0.009mol·min^-1(2)反應(yīng)速率隨著反應(yīng)的進(jìn)行，先逐漸增大再逐漸減小，后不變；原因：隨著反應(yīng)的不斷進(jìn)行，應(yīng)開始甲酸甲酯的濃度大，所以反應(yīng)速率較大，后隨著反應(yīng)進(jìn)行，甲酸甲酯的物質(zhì)的量濃度不斷減少，反應(yīng)速率不斷減慢，所以轉(zhuǎn)化率增大的程度逐漸減小，當(dāng)反應(yīng)達(dá)到平衡后，轉(zhuǎn)化率不變。

(3)1/7

(4)圖略。作圖要點(diǎn)：因?yàn)?i style='mso-bidi-font-style:normal'>T₂>T₁，溫度越高，平衡向逆反應(yīng)方向移動，甲酸甲酯的轉(zhuǎn)化率下降，T₂達(dá)到平衡時(shí)的平臺要低于T₁；另外溫度越高，越快達(dá)到平衡，所以T₂達(dá)到平衡的時(shí)間要小于T₁。

解析：(1)15min時(shí)，甲酸甲酯的轉(zhuǎn)化率為6.7%，所以15min時(shí)，甲酸甲酯的物質(zhì)的量為1-1.00mol×6.7%==0.933mol；20min時(shí)，甲酸甲酯的轉(zhuǎn)化率為11.2%所以20min時(shí)，甲酸甲酯的物質(zhì)的量為1-1.00mol×11.2%==0.888mol，所以15至20min甲酸甲酯的減少量為0.933mol-0.888mol=0.045mol，則甲酸甲酯的平均速率==0.045mol/5min==0.009mol·min^-1。

(2)從題給數(shù)據(jù)不難看出，平均速率的變化隨轉(zhuǎn)化率的增大先增大再減小，后保持不變。因?yàn)榉磻?yīng)開始甲酸甲酯的濃度大，所以反應(yīng)速率較大，后隨著反應(yīng)進(jìn)行甲酸甲酯的濃度減小，反應(yīng)速率減小，當(dāng)達(dá)到平衡時(shí)，反應(yīng)速率幾乎不變。

(3)由圖象與表格可知，在75min時(shí)達(dá)到平衡，甲酸甲酯的轉(zhuǎn)化率為24%，所以甲酸甲酯轉(zhuǎn)化的物質(zhì)的量為1.00×24%==0.24mol，結(jié)合方程式可計(jì)算得平衡時(shí)，甲酸甲酯物質(zhì)的量==0.76mol，水的物質(zhì)的量1.75mol，甲酸的物質(zhì)的量==0.25mol 甲醇的物質(zhì)的量==0.76mol

。所以K=(0.76×0.25)/(1.75×0.76)=1/7。

(4)因?yàn)樯�高溫度，反�?yīng)速率增大，達(dá)到平衡所需時(shí)間減少，所以繪圖時(shí)要注意T₂達(dá)到平衡的時(shí)間要小于T₁，又該反應(yīng)是吸熱反應(yīng)，升高溫度平衡向逆反應(yīng)方向移動，甲酸甲酯的轉(zhuǎn)化率減小，所以繪圖時(shí)要注意T₂達(dá)到平衡時(shí)的平臺要低于T₁。