A:用乙醇或CCl4可提取碘水中的碘单质
B:NaCl和SiC晶体熔化时,克服粒子间作用力的类型相同
C:24Mg32S晶体中电子总数与中子总数之比为1∶1
D:H2S和SiF4分子中各原子最外层都满足8电子结构
—Yesterday , my father bought me a new mobile phone as a present , but I don't know how to use it.
—Why not read the ________ first before using it ?
在正四面体P-ABC(所有棱长都相等)中,D,E,F分别是AB,BC,CA的中点,下面四个结论中不成立的是( )
济宁市的济宁、邹城、曲阜、兖州四座城市相互毗邻,呈现“组群式”特征,下列关于四个城市的说法,错误的是 ( )