当aym<acro时， ay=aYoN=1+[N]Ay≈cBy Boy =L=Bury Y CNBNY 准确滴定M的条件是cBY≥10 故 SMBY≥10°是分步滴定的判据 CNBNY当 α Y(H) < < α Y(N)时， N NY MY Y ' MY MY Y Y(N) NY N NY 1 [ N ] β β α β β α α β β c c = = = = + ≈ 准确滴定 M 的条件是 ' 6 c M β MY ≥10 故 6 N NY M MY ≥10 β β c c 是分步滴定的判据