A:3≤OM≤5
B:3≤OM<5
C:4≤OM≤5
D:4≤OM<5
回收利用是保护金属资源的一条有效途径,某工业废料含氧化铜和氧化铁,经过处理后可得到铜和硫酸亚铁溶液.主要流程如图:
已知:CuO+H2SO4═CuSO4+H20 Fe+Fe2(SO4)3═3FeSO4
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