只能表示一个化学反应的离子方程式是( ) A.H++OH-H2O B.+2H+H2O+CO2↑C.Zn(OH)2+2H+Zn2++2H2O D.Cu2++2OH-+Ba2++Cu(OH)2↓+BaSO4↓
在图中,开关闭合后磁感线的形状如图所示,请标出磁铁A的磁极和磁感线的方向。
环境污染已成为人类社会面临的重大威胁,各种污染数不胜数。下列名词与环境污染无关的是( ) ①富营养化 ②赤潮 ③酸雨 ④光化学污染 ⑤
若正棱锥的底面边长与侧棱长都相等,则该棱锥一定不是 ( ) A.三棱锥 B.四棱锥 C.五棱锥
we up with some other ways to solve this problem? A. Should; to come B. Ought; to come C. Ought; come D. Should; coming
某高中学生在研究中国服饰变化时收集到以下几个案例:①北魏孝文帝“更姓易服”;②唐女装“袒露”与宋女装“清雅”;③民国时期的“中山装”
People all over the world think (61)_________(high) of the Amber Room.. it had such an(62)________(amaze) history that (63)____________ (recent) Russians and Germans thought it was well worth (64)_
下列说法中正确的是( ) A.物体所受的合外力越大,其运动状态改变越快 B.物体运动的越快,就越不易停下来,所以惯性就越大 C.只要物体