试题与答案

图是电解CuCl2溶液的装置,其中c、d为石墨电极. (1)正极为______(

题型:问答题

题目:

图是电解CuCl2溶液的装置,其中c、d为石墨电极.

(1)正极为______(填“a”或“b”)阳极为______.(填“c”或“d”)

(2)阳极电极反应式为______检验该阳极产物的方法是______.

(3)电解一段时间后发现阴极增重6.4g,则外电路中通过的电子的物质的量是______摩尔,若该电解反应所需的电子全部由氢氧燃料电池提供,则至少需要消耗______L氢气(标准状况下)才能满足需要.

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A解析:解析 定位到表格“民间投资”一行,10月的值用1~10月值减去1~9月值:19727-17288=2439;4月的值用1~4月值减去1~3月值:7560-5418=2142;两者差值为:2439-2142=297。 故正确答案为A。 考点:数值计算型

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