将碳和氧化铁的混合物共71.2克加强热，碳和氧化铁恰好完全反应，则生成铁______克．
设71.2g碳和氧化铁的混合物中含有氧化铁的质量为x，生成铁的质量为y；
2Fe2O3+3C
4Fe+3CO2↑ 高温 .
320 36 224
x 71.2g-x y
则
=320 x
，36 71.2g-x
解得：x=64g；
则
=320 64g
，224 y
解得：y=44.8g；
故答案为：44.8．
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| Why is Jim allays running on the bus? Jim is a little boy. He 1 five years old. One day his mother 2 him to see his grandpa. His grandpa's home is very far 3 them, so they went. there 4 . There 5 only a few people on the bus. They all sat on 6 seats. Jim was very happy. He out of the window and talked 7 his mother. After a while; Jim started running on the bus. He ran and ran. " 8 are you always running? Please sit 9 " his mother said. "I want 10 my grandpa earlier (早点儿) I want the bus to be more faster (更 快). "Jim answered. | |||
| ( )1. A. has ( )2. A. takes ( )3. A. from ( )4. A. on a bus ( )5. A. was ( )6. A. they ( )7. A. for ( )8. A. What ( )9. A. in ( )10. A. to see | B. is B. took. B. off B. with a bus B. were B. them B. of B. How B. near B. to look | C. was C. talked C. to C. by a bus C. is C. their C. about C. Which C. down C. to meeting | D. were D. brought D. with D. by bus D. had D. theirs D. with D. Why D. up D. to watch |