When I was young, I wanted to be ________Olympic winner.[ ]
A. a
B. an
C. the
D. /
答案:B
下列离子方程式中,正确的是
A.Ca(ClO)2溶液中通入过量的CO2:Ca2++2ClO—+ CO2+H2O = CaCO3↓+ 2HClO
B.钠和冷水反应:Na + 2H2O = Na+ + 2OH- + H2↑
C.氯气和水反应:Cl2 + H2O = 2H+ + Cl- + ClO-
D.FeCl2溶液中滴加氯水:2Fe2+ + Cl2 = 2Fe3+ + 2 Cl-
水电厂采用的计算机监控方式有哪三种?