【单选题】N A 为阿伏加德罗常数的数值,下列说法中正确的是( )
A.
在密闭容器中加入l.5mol H2和0.5molN 2 ,充分反应后可得到NH 3 分子数为N A
B.
一定条件下,2.3g的Na完全与O 2 反应生成3.6g产物时失去的电子数为0.1N A
C.
1.0L的0.1 mol·L-1Na2S溶液中含有的S 2- 离子数为0.1N A
D.
标准状况下,22.4L的CCl 4 中含有的CCl 4 分子数为N A
【单选题】Nowadays, college students are seen waiting on tables, cleaning in stores, advertising in streets, teaching in families and doing whatever work they can find. It has become fashionable for college stu...
【单选题】Nowadays, college students are seen waiting on tables, cleaning in stores, advertising in streets, teaching in families and doing whatever work they can find. It has become fashionable for college stu...
【判断题】外部介质的分子或原子对晶体界面原子的作用力与晶体内部原子对界面原子的作用力相差越悬殊,则表面能越小。
【简答题】Frank Work Experience went to a p___(1)___ company (私营公司) changed to a Sino –Japanese joint-venture enterprise(中日合资企业) and worked as a __(2)__ ______ two years later, moved on to a c___(3)____ compan...