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A common biological buffer is a phosphate buffer which involves the equilibrium between H2PO4- and HPO4-2,...

A common biological buffer is a phosphate buffer which involves the equilibrium between H2PO4- and HPO4-2, with a pKa at 25 celcius of 6.86. Describe in words how you would prepare 500. mL of 0.250 M phosphate buffer at pH 7.2 given 500 mL each of 0.250 M NaH2PO4 and 0.250 M Na2HPO4 at 25 celcius.

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