问题 选择题

下列关于卤族元素由上到下性质递变的叙述,正确的是[ ]

①单质的氧化性增强 ②单质的颜色加深 ③气态氢化物的稳定性增强

④单质的沸点升高 ⑤阴离子的还原性增强

A.①②③

B.②③④

C.②④⑤

D.①③⑤

答案

答案:C

探究题

实验题(5分)

修正液是同学们常用的一种文具,打开后,有刺激性的气味。我们不禁要问:修正液对人体有害吗?请你设计一个实验,对这个问题进行探讨。

【实验材料】修正液、小白鼠6只、米饭、水、关小白鼠的笼子。

【提出问题】                                                                      

【作出假设】                                                                      

【设计方案】                                                                                                                                       

                                                                                                                                   

                                                                                                                                 

【现象】                                                                            

【结论】                                                                         

单项选择题