下列实验现象的描述正确的是（ ）
A．硫在空气中燃烧产生蓝紫色火焰
B．氢气在氧气中燃烧产生蓝色火焰
C．铁丝在空气中燃烧，火星四射，生成了一种黑色固体
D．甲烷在空气中燃烧，产生明亮的蓝色火焰
A、硫在空气中燃烧，产生淡蓝色火焰，故选项说法错误．
B、氢气在氧气中燃烧，产生淡蓝色火焰，故选项说法错误．
C、铁丝在空气中只能烧至发红，不会产生火星，故选项说法错误．
D、甲烷在空气中燃烧，产生明亮的蓝色火焰，故选项说法正确．
故选D．
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| I am a big peacemaker. I would much rather take the blame for just about anything than get into an 1 . However, Lose-Win ( 委曲求全) is weak. It's easy to get 2 . On and easy to gtve tn. My 3 with my mom all started one day when she said to me sarcastically(挖 苦),"Wow, you're sure 4 today."I took it so seriously that I decided to 5 , myself off from her and never talk back to her. So every time she would say something, 6 I disagreed with her I would just say,"Okay, 7 you want, Mom" But I 8 got cold quickly. One night I just 9 talking to my mom about the school homework and she said," 'Oh, that's 10 "and then went back to mop the floor. "Don't you ever 11 ?"I thought. But I didn't say anything and stormed off. She had no idea I was 13 .She would have been willing to 12 to me had I told her how important it was to me. 14 , I just blew up." Mom, this has got to 15 . You tell me everything you want me to do and I just do i' because it's 16 than quarrelling. Well, I'm sick of it." This all came as a 17 to her. After my blowup, we felt like we were starting all over in our 18 .But it's getting better all the time. We discuss things now and I always 19 my feelings with her. If you adopt Lose-Win as your basic attitude toward life, you'll be 20 your true feelings deep inside. And that's not healthy. | |||
| ( )1. A. apology ( )2. A. held ( )3. A. fights ( )4. A. lucky ( )5. A. close ( )6. A. as if ( )7. A. something ( )8. A. really ( )9. A. finished ( )10. A. true ( )11. A. agree ( )12. A. impatient ( )13. A. talk ( )14. A. Anyway ( )15. A. happen ( )16. A. worse ( )17. A. surprise ( )18. A. hardship ( )19. A. share ( )20. A. hurting | B. argument B. focused B. problems B. polite B. cut B. as long as B. whatever B. even B. kept B. impossible B. promise B. frightened B. explain B. After a while B. change B. easier B. pleasure B. relationship B. have B. leaving | C. emergency C. moved C. quarrels C. troublesome C. set C. even though C. nothing C. eagerly C. avoided C. nice C. scold C. sure C. come C. At last C. last C. more C. gift C. faith C. discuss C. storing | D. enemy D. stepped D. talks D. clever D. take D. so that D. too much D. maybe D. remembered D. fair D. care D. upset D. get D. Once again D. stop D. safer D. harm D. life D. express D. hiding |