A:开始生成蓝色沉淀,加入过量氨水时,形成无色溶液
B:Cu(OH)2溶于浓氨水的离子方程式是Cu(OH)2+4NH3 Cu(NH3)42++2OH-
C:开始生成蓝色沉淀,加入氨水后,沉淀溶解形成深蓝色溶液
D:开始生成Cu(OH)2,之后生成更稳定的配合物
如图,已知矩形ABCD∽矩形ECDF,且AB=BE,那么BC与AB的比值是( )
欧洲西部畜牧业发达的主要原因是( )
Yesterday I was shopping for a few items(物品).With nothing to do at home, my son, who just left university, was ready to go together with me. As I pushed the basket towards the register(收银机),I checked my items to see how many I had, thinking I might go to the Express Line(快速通道)where the sign said“Ten items or less”. I started to go to that line and my son said,“Mon, you have twelve items!”I said,“You know, but they’re close.” He said,“Why are you in such a hurry to get home? You should go to the Regular Line because you have over ten items.” Knowing he was right. I agreed and then pushed the basket to the next line. So I was waiting for my turn there and I was just removing my items from the basket to pay for them when a young man came up behind me in line with two items. I just left the Express Line because I had too many and now I really wanted to get finished. Again, my son came up.“Mom, he has only two items and the Express Line is very long now. Won’t you just let him go first?”I agreed, and the young man smiled widely and thanked me several times. It felt good to be with my son and have him remind me not to live a hurried life. Do what’s right and also be kind. I really take pride in him.