Buffer A: 0.3M NaCl, 0.03M sodium citrate pH 7.0 (2xSSC)

Buffer B: 0.6M KCl, 75 mM Tris-HCl pH 9.0-9.5

I know experimentally that Buffer B has higher ionic strength as compared to Buffer A, as I get DNA strand separation at a certain temperature with Buffer A but not with Buffer B.

I would like to know the exact ionic strength of these two buffers, but I am not sure about the calculations. I know I need to use the formula I=1/2 ​∑(ci​⋅zi2​) but I am not sure how to account for the dissociation of Tris-HCl and sodium citrate (Na3C6H5O7), for example.

Can you help me with the math here? :)