I got confused in dealing with ionic strength. 1. The problem statement, all variables and given/known data In calculating ionic strength, do we consider the composition of the solution? Take for example: Solution 1 has 20 ml of 0.1 M NaCl and 35ml of 0.2 M CaCl Solution 2 has 25 ml of 0.1 M NaCl and 30 ml of 0.2 M CaCl Would the ionic strength be different for the two or be the same? In other words, does ionic strength depends on the composition? 2. Relevant equations Ionic Strength: I = 0.5*sum(c*z^2) 3. The attempt at a solution Ionic Strength: I = 0.5*sum(c*z^2) I = 0.5*(0.1*(+1)^2+0.2*(+1)^2+0.1*(-1)^2+0.… I = 0.5*(0.6) I = 0.3 So, are the two solutions going to have an ionic of 0.3 or would they have different ionic strengths? Thanks in advance.