题目

(11·钦州)由若干个相同的小立方体搭成的几何体的三视图如图所示,则搭成这个几何体的小立体的个数是A.3                       B.4                             C.5                          D.6  答案:A解析:略 已知下列热化学方程式:①C(s)+O2(g)==CO2(g)△H= —393.5kJ/mol②CO(g)+ 1/2 O2(g)="=" CO2(g)△H= —283.0kJ/mol③2Fe(s)+3CO(g)==Fe2O3(s)+3C(s)△H= —489.0kJ/mol则4Fe(s)+3O2(g)==2Fe2O3(s)的反应热ΔH为(   )A.-1641.0kJ/molB.+3081kJ/molC.+663.5kJ/molD.-2507.0kJ/mol
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