题目

由下列实验对应的现象推断出的结论正确的是选项实验现象结论A将红热的炭放入浓硫酸中产生的气体通入澄清的石灰水石灰水变浑浊炭被氧化成CO2B将稀盐酸滴入Na2SiO3溶液中溶液中出现凝胶非金属性：Cl>SiCSO2通入BaCl2溶液，然后滴入稀硝酸有白色沉淀产生，加入稀硝酸后沉淀溶解先产生BaSO3沉淀，后BaSO3溶于硝酸D向某溶液中滴加KSCN溶液，溶液不变色，再滴加新制氯水溶液显红色原溶液中一定含有Fe2＋A.A B.B C.C D.D 阅读下列短文, 从所给的四个选项中, 选出最佳答案。     These days experiences, like many other things, are becoming increasingly expensive. One has got to pay a lot to get even an ordinary one.     Not long ago, I wanted to invite my friends to a lunch. What we really need was a good and quiet place for a talk, not a big meal. So I selected one for people only who belong to a particular club. I　　 belong to the club, too. What could be nicer? "Let's go to the club," I told my friend.     When I ordered a day in advance, I was asked whether I would eat a 20 yuan or 30 yuan lunch. I said, "30 yuan". I didn't realize until I was asked to pay after the lunch, that "30 yuan" means "30 yuan for persons each."     There were five people that day, and all of us were surprised by the quality of the 30 yuan meal (for all, we thought). The bill came at last: it was 216.40 (150 for the five of us plus the money for drinks, fruits and air conditioning). I paid the bill without a word.     What could I say? It was not the club's fault. It was my own ignorance (无知) that made me pay the largest bill in my life.     On the whole, it was not so bad; we had a good lunch and a quiet place. Besides, the experience will help in later years.     To support my idea, I have developed my own calculation (算法): 30 yuan for the lunch and 186.40 for the experience. This paid experience has made me ten times wiser. 1. Now many things are becoming ______________. [　　] A. less expensive　　　　 B. not so expensive as before 　　 C. as expensive as before　　 D. more expensive　　 2. I ordered a lunch ________________. [　　] A. the day before　　　　 B. so as to have a big lunch 　　 C. so that we could have a grand party 　　 D. in order to introduce my friend to the members of the club which I belong to 3. I had thought that I had ordered a meal that cost ____________. [　　] A. me 20 yuan　　 B. me 30 yuan C. us 20 yuan each D. us 30 yuan each 4. What do you think makes me pay the largest lunch bill in my life? [　　] A. My fault.　　　　 B. My ignorance.　　　　 C. The club that had managed to make its customers misunderstand. D. My friend's fault.　　 5. "This paid experience has made me ten times wiser." expressed ________. [　　] A. the writer's thanks to the club 　　　　 B. the writer's pleasure to ten times wiser 　　 C. the writer's modesty　　　　 D. the writer's anger