能正确表示下列反应的离子方程式为
A:用铁棒作阴极、炭棒作阳极电解饱和氯化钠溶液:2Cl-+2H2OH2↑+Cl2↑+2OH-
B:NH4HCO3溶于过量的NaOH溶液中:HCO3-+OH-=CO32- +H2O
C:将1mol/L NaAlO2溶液和1.5mol/L的HCl溶液等体积互相均匀混合:3AlO2-+ 6H+= 2 Al(OH)3↓+ Al3+
D:NaClO溶液与FeCl2溶液混合:Fe2+ + 2ClO-+ 2H2O = Fe(OH)2↓ + 2HClO
读短文,填空
Hello ! My name is Amy .I'm a girl .I'm from England. Look !This is my father and this is my mother .My father is a teacher. My mother is a doctor .The boy is my brother .He's eight .He's a student .who's this girl ? Can you guess??
如图,将薄纸片置于下唇底部,沿着纸片的上表面吹气,纸片升起,可知吹气过程空气对纸片上表面的压力 ____ 下表面的压力(选填“大于”、“等于”、“小于”),证明气体压强与流速的关系是 ____ .
我们能用什么方法,使静止的小球运动起来?
____ (not finish) the homework, the little girl doesn't dare to go to school.
如图,在□ABCD中,延长AB到点E,使BE=AB,连接DE交BC于点F,则下列结论不一定成立的是( )