下列叙述正确的是（ ）
A．硅元素在自然界中以游离态存在
B．氨气是工业制取硝酸的重要原料
C．铝是金属，与强碱不能发生反应
D．陶瓷、玻璃、水泥都属于碳酸盐产品
A、Si在自然界中的存在既有单质硅又有含硅的化合物，所以既有游离态又有化合态，故A错误；
B、氨气催化氧化可以获得一氧化氮，然后转化为二氧化氮，和水反应可以获得硝酸，氨气是工业制取硝酸的重要原料，故B正确；
C、金属铝既能和强酸反应又能和强碱反应，故C错误；
D、陶瓷、玻璃、水泥的主要成分中均含有硅酸盐，属于硅酸盐产品，故D错误．
故选B．
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| Mrs. Ball had a son. His name was Mick. She __1__ him very much and as he was not a __2__ child, she was always __3__ that he might be ill, __4__ she used to take him to see the best __5__ in the town four times a year to be looked __6__. During one of these __7__, the doctor gave Mick all kinds of tests and then said to him, "Have you had any __8__ with your nose or ears recently?" Mick __9__ for a second and then answered, "Yes, I __10__." Mrs. Ball was very __11__. "But I'm sure you have __12__ told me that, Mick!" She said worriedly. "Oh, really?" Said the doctor __13__. "And what trouble have you with your nose and ears, my boy?" "Well," answered Mick, "I always have trouble with them when I'm __14__ my sweater off, because the __15__ is very tight." | |||
| ( )1. A. loved ( )2. A. rich ( )3. A. afraid ( )4. A. which ( )5. A. player ( )6. A. round ( )7. A. talks ( )8. A. answer ( )9. A. waited ( )10. A. did ( )11. A. excited ( )12. A. already ( )13. A. angrily ( )14. A. turning ( )15. A. collar | B. hated B. clever B. surprised B. for B. teacher B. over B. years B. thing B. thought B. will B. interested B. just B. seriously B. taking B. nose | C. missed C. strong C. glad C. but C. doctor C. for C. visits C. word C. stood C. have C. pleased C. never C. happily C. keeping C. mouth | D. cared D. happy D. sure D. so D. lawyer D. after D. stays D. trouble D. looked D. do D. surprised D. always D. carefully D. putting D. ear |