问题 选择题

下列变化过程,属于放热过程的是(  )

A.液态水变成水蒸气

B.酸碱中和反应

C.弱酸电离

D.NH4Cl晶体与Ba(OH)2•8H2O混合搅拌

答案

A.液态水变成水蒸气是吸热过程,故A错误;

B.酸碱中和反应是放热反应,故B正确;

C.弱酸电离是吸热过程,故C错误;

D.NH4Cl晶体与Ba(OH)2•8H2O反应是吸热反应,故D错误.

故选B.

单项选择题
综合题

       芳芳和圆圆参加研究性学习小组,她们选择了“评价辛亥革命”的课题进行调查研究学习。现遇到了一些问题,请你为她们提供帮助。

(1)应通过哪些途径去收集相关历史资料?

                                                                                                                                                            

                                                                                                                                                            

(2)她们在研究学习中认为辛亥革命既成功了,又失败了。你认为对吗?并说说理由。

                                                                                                                                                             

                                                                                                                                                            

                                                                                                                                                            

(3)孙中山身上有哪些值得我们学习的思想品质?