题干

铜是人类最早发现和使用的金属之一,铜及其合金的用途广泛.粗铜中含有少量铁、锌、镍、银、金等杂质,工业上可用电解法精炼粗铜制得纯铜,下列叙述正确的是(  )(已知:氧化性Fe2+<Ni2+<Cu2+


A:粗铜作阳极,其电极反应式:Cu2++2e=Cu

B:电解过程中,电解质溶液中c(Cu2+)不变

C:电解后,阴极上还附有极少量的Fe和Ni

D:电解后,可用阳极泥来提炼金、银等贵金属

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D

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