nHCl=0.1x0.5=0.05mol，Fe为0.1molHCl不足，按HCl计算Fe + 2HCl=FeCl2+H2...........2....................22.4...........0.05.................x2/0.05=22.4/x，x=0.56升0.05mol的H+_——0.05molH0价转移0.05mol电子
