题目

On the first day of your Senior High you must meet many new classmates. Do you want to make friends with them? Do you know how to make friends with them? The following article will tell you how to do it. Making friends is a skill. Like most skills, it improves   21   practice. If you want to meet people and make friends you must be   22   to take action. You must first go to places where there are people. You won’t make friends   23   at home alone. Join a club or group, for talking with those who   24   the same experience as you is easier, and   25   them in s2．铁、稀硫酸、Ba（OH）2溶液、CuSO4溶液是中学化学常见的物质，这四种物质间的反应关系如图所示，图中两圆相交部分（A、B、C、D）表示物质之间可能发生的反应，请回答下列问题：（1）图中ABCD 相交部分，不能发生置换反应的是AB（2）B反应的离子方程式为Cu2++2OH-=Cu（OH）2↓（3）D反应的离子方程式为Fe+2H+=Fe2++H2↑（4）除去CuCl2溶液中的稀盐酸需要加入适量的试剂为CuO写化学式），写出其反应原理的化学方程式CuO+2HCl=CuCl2+H2O