题目

It is Children's Day,? A . was it B . isn't it C . is it 答案：B向50 mL 18 mol·L－1的H2SO4溶液中加入适量的铜片并加热。充分反应后，被还原的H2SO4的物质的量为 A．小于0.45mol                     B．等于0.45 mol   C．在0.45～0.90 mol之间             D．大于0.45 mol