Buffers of constant ionic strength No added electrolyte

1 Buffers of constant ionic strength. No added electrolyte. 

Having calculated the ionic strength it becomes possible to convert a thermodynamic pATa given in Appendix III to a practical pATa for the given ionic strength. This is done by using a convenient form of the Debye-Huckel equation, such as that due to Davies (1938) 

Values of the term within braces can be read directly from Table 2.3. 

The concentration ratio for the buffer species can now be obtained by using the rearranged forms of the Henderson-Hasselbalch equation, 

BH /B , etc. This computer programme was tested for a number of buffer systems and was found to give good agreement with published values. For example, it 

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