试题与答案

某合金(仅含铜、铁)中铜和铁的物质的量之和为y mol,其中Cu的物质的量分数为

题型:选择题

题目:

某合金(仅含铜、铁)中铜和铁的物质的量之和为y mol,其中Cu的物质的量分数为a,将其全部投入50 mL b mo1·L-1的硝酸溶液中,加热使其充分反应(假设NO是唯一的还原产物)。下列说法正确的是[ ]

A.若金属有剩余,在溶液中再滴入硫酸后,金属不会再溶解

B.若金属全部溶解,则溶液中一定含有Fe3+

C.若金属全部溶解,且产生336 mL气体(标准状况),则b=0.3

D.当溶液中金属离子只有Fe3+、Cu2+,则ab的关系为:b≥80 y (1-a/3)

答案:

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