用2000t含杂质20%的赤铁矿石，理论上可以炼出含杂质4%的生铁多少吨？
2000t矿石中含氧化铁的质量为：2000t×（1-20%）=1600t
设1600t氧化铁理论上可炼出铁的质量为x
Fe2O3+3CO
2Fe+3CO2 高温 .
160 56×2
1600t x
=160 56×2 1600t x
x=1120t
折合为含杂质4%的生铁的质量为：1120t÷（1-4%）=1166.7t
答：用2000t含杂质20%的赤铁矿石，理论上可以炼出含杂质4%的生铁1167.7吨．
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| Now that I am no longer young, I have friends whose mothers have passed away. I have heard these sons and daughters say they never fully appreciated their mothers 1 it was too late to tell them. I am blessed with the dear mother who is still alive. I 2 her more each day. My mother does not change, but I 3 . As I grow older and wiser, I realize 4 an extraordinary person she is. How 5 that I am unable to speak these words in her 6 , but they flow easily from my pen． How does a daughter begin to thank her mother for life itself ? For the love, patience and just 7 hard work that go into 8 a child? For running after a toddler (学走步的小孩), for understanding a 9 teenager, for tolerating a college student who knows 10 ? For waiting for the day when a daughter 11 how wise her mother really is? How does a 12 woman thank a mother for 13 to be a mother? For being ready 14 advice (when asked) or remaining 15 when it is most appreciated? For not saying, "I told you so," when she could have uttered these words 16 ? For being 17 herself-loving, thoughtful, patient, and forgiving? I don't know how, dear God, except to ask you to bless her as richly as she 18 and to help me live up to the example she has 19 ． I pray that I will look as good in the eyes of my children as my mother 20 in mine． | |||
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