I realize she can be very troublesome, but ______ I think you should apologize for being so angry with her. A.all the same B.once in a while C.in actual fact D.all the time 答案:A用石墨电极电解100 mL H2SO4与CuSO4的混合溶液,通电一段时间后,两极均收集到2.24 L气体(标准状况),则原混合溶液中Cu2+的物质的量浓度为 mol·L-1。