已知：含Fe2+的溶液与铁氰化钾K3[Fe(CN)6]溶液反应生成具有特征蓝色的铁氰化亚铁沉淀，离子方程式为：3Fe2+ + 2[Fe(CN)6]3-=== Fe3[Fe(CN)6]2↓。现用下图装置在浸有铁氰化钾浅黄色溶液的滤纸上写出蓝色的字“神奇的化学”，据此判断下列说法正确的是
A．直流电源的a极是阴极
B．直流电源的b极是负极
C．阳极反应为：[Fe(CN)6]3-+ e-==Fe2+ +6CN-
D．“电笔”笔尖材料是铁，其电极反应为：Fe-2e-===Fe2+
答案：D
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| Long long ago, there was a small village. This village had a 1 tradition. At the beginning ofevery year, any boy who had reached the age of majority (成年)was given land and money to build a home. The boy had to 2 his home before winter. If his home failed to endure thecold weather in winter, the villagers could not 3 him inany way. One 4 , Paul and Mare reached their majority. They 5 their land and money and decided to search nearby villages for ideas on building their homes. In each village, they found the nicest 6 and talked to the owners. Each owner gladly offered 7 . After Marc saw several homes, he 8 the best ideas and went back to his own land. Paul, 9 , continued collecting more ideas. Soon he had so many great ideas that he began to 10 some of them. But he always believed he could find even better ideas in the next village. Marc began building his home. He had several false starts, 11 his home gradually rose from his land. By fall, Marc had finished his home. It wasn't perfect,but it was strong and he could 12 it later. Paul enjoyed all the beautiful homes and 13 with home owners. The first snow came and Paul, realizing he was running out of time, 14 back to his land. He built the best home he could in the time he had, but it was 15 . The first winter storm destroyed his home and he froze to 16 .The villagers mourned for him. Marc 17 the winter. Each year, Marc searched for other good ideas he could use to make his own home look better. He became a leader in the village, 18 a family, and lived a happy, content life. We all build and improve our own mental homes. It's 19 and fun for us to search for ideas from other mental home owners, but we only improve our own mental home if we actualIy 20 the best ideas. | |||
| ( )1. A. strange ( )2. A. find ( )3. A. help ( )4. A. winter ( )5. A. exchanged ( )6. A. girls ( )7. A. rooms ( )8. A. expected ( )9. A. similarly ( )10. A. forget ( )11. A. because ( )12. A. repair ( )13. A. conversations ( )14. A. drove ( )15. A. weak ( )16. A.blindness ( )17. A. experienced ( )18. A. brought ( )19. A. slow ( )20. A. realize | B. hopeful B. make B. encourage B. summer B. received B. jobs B. drinks B. gathered B. finally B. believe B. although B. rebuild B. achievements B. rushed B. funny B. death B. loved B. earned B. easy B. bring | C. literary C. complete C. scold C. autumn C. recognized C. houses C. attention C. created C. however C. replace C. but C. sell C. struggles C. flew C. small C. sadness C. survived C. contacted C. dangerous C. collect | D. cultural D. buy D. persuade D. spring D. advice D. presents D. advice D. understood D. furthermore D. doubt D. so D. improve D. arguments D. moved D. amazing D. illness D. spent D. raised D. special D. apply |