Weak Acids and Their Corresponding Strong Bases

2 Strong Acids and Their Corresponding Weak Bases 4.1.2.1 Strong Acids in High Concentration 

This means that the real pH will be somewhat left of the pH-coordinate of Pi, as to the right of this, the sum Cqh- + Cb- is always larger than Cjj o+ other words, in addition to the HsO concentration produced by the protolysis of HB, there is also some HsO from the autoprotolysis of water). The diagram shows that the concentration of OH is at the point Pi and also, to the left to it, much smaller than the concentration of (cf. point P2). Hence it is a good approximation to write  

This means that the pH-coordinate of the crossing point of the HsO and B lines gives in very good approximation the pH of the solution. 

A simplified equation can be easily derived when the amount balance (Eq. (18)) is taken in to account  

Simplified equation for a strong acid in high concentration  

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