题目

下列反应的离子方程式书写正确的是 A．氯化钙溶液中通入二氧化碳气体：Ca2++CO2+H2O=CaCO3↓+2H+B．次氯酸钙溶液中通人少量SO2气体：Ca2++2ClO一+SO2+H2O=CaSO3↓+2HClOC．醋酸和碳酸氢钠溶液混合：CH3COOH+HCO3-=CO2↑+H2O+CH3COO-D．碳酸氢镁溶液中加入过量石灰水：Mg2＋+2HCO+Ca2＋+2OH－==CaCO3↓+2H2O+MgCO3↓  答案：C解析:略 第二节、完形填空（本题共20小题，每题1分，满分20分）阅读下面短文，从短文后所给各题的A、B、C和D四个选项中，选出可以填入空白处的最佳选项。Mr. West wanted to buy his wife a Christmas present, but he was always very   21   , so he was never able to find time to go to the shops. At last, when it was the week   22   Christmas, and the shops were very crowded, he decided that he could not   23  any longer. He worked in an office, and usually  24  lunch in a restaurant, but one day he bought some sandwiches, ate 25  quickly and went out to a big shop near his  26 during his lunch hour.The shop was full of women, who were also buying   27   during their lunch hour. Mr. West stood   28   at the edge of a crowd of 29  who were pushing forward to try to get to the people who were  30   necklaces and earrings. He tried to move forwards slowly, taking his turn with the others, but more and more women were 31 into the shop the whole time and pushing selfishly (自私地) 32  him. After half an hour, he was just as 33    from the people who were selling the necklaces as he had been when he came in, and his lunch hour was coming to 34   , so he decided to change his 35   of doing things: he put his head down, gave a sudden loud shout and started to  36  his way towards the 37     of the crowd as hard as he could.The women around him became very 38   when they saw what he was doing, and began to scold (责备) him. “Why can’t you behave (做事) like a  39  ?”, they shouted.“Ladies,” he answered them, “I have been behaving like a gentleman for the past half hour, and it has got me   40  , so now I am starting to behave like a lady!”(   )21. A. lazy            B. unwilling           C. busy              D. forgetful(   )22. A. before         B. around           C. behind             D. after(   )23. A. work           B. stay                C. wait               D. think(   )24. A．had             B．have               C．eat                           D．took(   )25. A. it                B. them               C. that                            D. those (   )26. A. car                 B. house              C. restaurant          D. office (   )27. A. presents        B. sandwiches          C. clothes            D. food           (   )28. A. alone           B. quietly             C. politely            D. freely(   )29. A. women          B. children            C. men              D. strangers(  )30. A. examining     B. selling              C. choosing           D. buying(   )31. A. going              B. entering            C. coming            D. running(   )32. A. behind             B. past              C. over             D. against(   )33. A. near          B. up                C. far               D. out (   )34. A. a top           B. an end              C. measure           D. the limit(   )35. A. idea            B. measure            C. way              D. plan(   )36. A. step            B. push               C. go               D. pull(   )37. A. front           B. edge               C. center            D. back(   )38. A. surprised        B. afraid              C. angry             D. nervous(   )39. A. gentleman           B. lady              C. woman                 D. man(   )40. A. anywhere        B. nowhere            C. somewhere        D. everywhere