题目

下列有关电化学装置完全正确的是（ ）ABCD铜的精炼构成铜锌原电池铁上镀银防止Fe被腐蚀 A. A B. B C. C D. D 答案：【答案】D【解析】A．粗铜精炼时，粗铜作阳极，纯铜作阴极，且电解质溶液是可溶性的铜盐，故A错误；B．含有盐桥的原电池中，电极材料和电解质溶液中金属阳离子属于同一元素，铜锌原电池中，硫酸铜溶液中电极应该是铜电极，硫酸锌溶液中电极应该是锌电极，故B错误；C．电镀时，镀层金属作阳根据对话内容，用适当的词语或句子补全对话。 （At the library） A：Hello，can I help you? if：Yes，please．Have you got the history of Chinese Literature? A：You are so  1  ．Someone has just returned it．  2   ，please，I'll go and get it for you．．．Here you are． B：Thank yon．By the way， 3  ? A：A month． B：Can I keep it a little   4  if I can't finish it on time． A：Yes，you can．Please take care of your book．Don't lose it，or you will have to  5  for it． B：Thanks a lot．Good bye． A ：Bye-bye．