题目

在下列反应中,二氧化碳作氧化剂的是( ) A. Ca(OH)2+CO2=CaCO3↓+H2O B. CO2+C2CO C. 2Fe2O3+3C4Fe+3CO2↑ D. C+2H2O(g)2H2+CO2 答案:【答案】B 【解析】 【详解】A. Ca(OH)2+CO2=CaCO3↓+H2O反应中,没有元素化合价的变化,不是氧化还原反应,A错误; B. CO2+C2CO反应,CO2中C元素的化合价降低,则CO2为氧化剂,B正确; C. 2Fe2O3+3C4Fe+3CO2↑中C元素化合价升高,则C为还原剂,CO2为氧化产物,C.错误; D.C+2H2O(g)2H2+CO2反应中,C元素的化合价升高, 补全对话, 每空一词 A:Tomorrow is Sunday.  1   do you want to do? B:I want to go to the zoo.Do you want to go   2   me? A:  3   , I   4  .  5   shall we go there? B:Let's make it 9∶00 in the morning. A:  6   can I meet you? B:At the gate of our school. A:  7   animals can we see there? B:We can see many interesting animals. A:  8   you like elephants? B:Yes,   9   do. A:I like elephants,   10  . 1.________ 2.________ 3.________ 4.________ 5.________ 6.________ 7.________ 8.________ 9.________ 10.________
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