有FeO和Fe2O3的混合物，在H2流中加热充分反应后，冷却称得剩余固体比原混合物质量减少1.6 g，若将同质量的混合物与盐酸反应，欲使之完全溶解，需1 mol·L-1的盐酸的体积为( )
A．400 mL
B．200 mL
C．100 mL
D．条件不足，无法计算
答案：B
因混合物被H2还原后生成Fe单质，减少的是氧的质量，混合物中含氧元素：
="0.1" mol，而原混合物与盐酸反应生成的H2O中，氢元素的物质的量为氧元素的2倍，故n(H+)="0.2" mol，需1 mol·L-1的HCl 200 mL。
| 阅读理解。 | ||||
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| 1. What's special about the Fishing Garden? | ||||
| A. It is inside a beautiful garden. B. It's quiet and nearby downtown. C. It helps people kill time. D. It provides free wireless internet service. | ||||
| 2. It took Chang'e-l about ________ to send its first photo back to the earth. | ||||
| A. a week B. two weeks C. a month D. a year | ||||
| 3. What does the writer try to tell us in Passage 3? | ||||
| A. Two heads are better than one. B. Many hands make light work. C. Judge not from appearance. D. Don't put all your eggs in one basket. | ||||
| 4. From the fourth passage, we can infer that in France and Britain, ________. | ||||
| A. people think more of performing arts than sport B. the meaning and appeal of sport are taken seriously C. sport is regarded as important as the performing arts D. sport has been judged by the normal standards of public life |