This program fits data to the equations: Alkaline sigmoid (kobs = k/(1+[H]/Ka) and Acid sigmoid (kobs = k/(1+Ka/[H]).
When "Fit with estimates" is selected you must input the initial estimates of kobs and the pKa. The experimental data is then fitted using an iterative, non linear least-squares regression program.
Results can be printed, saved as a text document or copied and pasted into other applications