Titration of Tris- hydroxymethyl amino Methane

For standardizing acid solutions, primary standard tris-(hydroxymethyl)amino methane, THAM (also referred to as TRIS), can be used. Its formula is 

It has a high formula weight (121.14), is stable at moderate drying oven temperatures, and is available in pure form. The reaction with an acid involves the acceptance of one hydrogen by the amine group, -NH2  

FIGURE 5.9 Titration curve for the titration of KHP with NaOH. 

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