38. Solution to Chemistry Problem

3. In standard CdSO4 solutions with different Cd2 activities, the electrode potentials of the cadmium-selective electrode relative to the silver chloride electrode were measured
acd, mol/l 1.0*10-1 1.0*10-2 1.0*10-3 1.0*10-4 1.0*10-5
E, mV 75.0 100 122 146 170
A calibration graph was constructed in the coordinates E - paCd based on these data. The 10.00 ml of the cadmium salt solution under study was diluted with water to 50.00 ml in a volumetric flask and the electrode potential of the cadmium-selective electrode was measured in the resulting solution - Ех, mV 159
Determine the activity (mol/l) of the cadmium salt solution under study