问题 选择题

已知反应FeO(s)+C(s)= CO(g)+ Fe(s)的△H>0,(假设△H,△S不随温度变化而变化),下列叙述中正确的是:(   )

A.低温下为自发过程,高温下为非自发过程

B.高温下为自发过程,低温下为非自发过程

C.任何温度下为非自发过程

D.任何温度下为自发过程

答案

答案:B

问答题

       在中国近现代史上,中国社会性质发生过三次变化。请你指出1949年—1956年底中国社会性质发生的两次变化?简要说明每次变化的主要原因是什么?

                                                                                                                                                             

                                                                                                                                                             

                                                                                                                                                             

                                                                                                                                                             

                                                                                                                                                              

                                                                                                                                                              

填空题