A. The measured pH of a 0.100 M HCl solution at 25 degrees Celsius is 1.092. From this information, calculate the activity coefficient of H+.B. The measured pH of a solution of 0.010 HCl and 0.090 KCl at 25 degree Celsius is 2.102. Calculate the activity coefficient of H+ in this solution. C. Why does the pH change in part B relative to that in part A?

activity coefficient

activity coefficient

The change in pH in part A = 0.092

The change in pH in part B =  0.102

Explanation:

From the given information:

pH of HCl solution = 1.092

Activity of the pH solution [a] =

[a] = 0.0809 M

Recall that [a] = × C

where;

 = activity coefficient

C = concentration

Making the activity coefficient the subject of the formula, we have:

B.

The pH of a solution of HCl and KCl = 2.102

[a] =

[a] = 0.00791 M

activity coefficient

C. The change in pH in part A = 1.091 - 1.0 = 0.092

The change in pH in part B = 2.102 -2.00 = 0.102

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)