A.10ml样+8mlCMC放置5min,再加0.5ml氨水和0.5ml柠檬酸铁铵放置5minB.10ml样+8mlCMC+0.5ml氨水+0.5ml柠檬酸铁铵放置10minC.10ml样+8mlCMC放置5min,再加1.0ml氨水和0.5ml柠檬酸铁铵放置5minD.10ml样+8mlCMC+0.5ml氨水+0.5ml柠檬酸铁铵,用DI水定容至25ml混匀放置10min
A.用石英比色皿,波长600nm处测量B.用玻璃比色皿,波长600nm处测量C.用石英比色皿,波长660nm处测量D.用玻璃比色皿,波长700nm处测量
A.用玻璃滤纸过滤并用具塞三角瓶震荡除气B.倒入到250ml 的三角瓶中,加上搅拌子在搅拌器上搅拌十分钟C.用802滤纸过滤并用具塞三角瓶震荡除气D.测量前不用除气