现有等体积的Ba(OH)2、NaOH和NH3·H2O三种溶液,将它们分别与V1L、V2L、V3L等浓度的盐酸混合,下列说法中正确的是
白色公羊和白色母羊交配生下一只黑色小羊。假如一胎能生3只,3只小羊都是黑羊的几率是( ) A、0 B、1/512 C、
下列化学用语书写正确的是() A.两个氢分子:2H B.2个硫酸根离子:2SO C.水中氧元素的化合价为-2:H2 D.两个氮
We must do what we can do to keep the b of nature.
---Do you know Mrs. Yang ? ---Yes. When I worked in that international company, I with her twice. A.had talked B.talked C.have talked
―Are you still busy? ―Yes, I ________ my work, and it won’t take long. A. just finish B. am just finishing C. have just finished
下列各句中,没有语病的一项是( )A.《哈利·波特》中文版一经出版,便深受广大中学生读者所欢迎,短短九个月时间里,该书便重印了九次