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# Preparing a Buffer Solution

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Calculate the mass (g) of pure Na3AsO4 (s) and volume (mL) of 1.50 M HCl that are required to make 100.0 mL of a buffer solution at a pH of 6.80 and an H2AsO4-(aq) concentration of 0.100 M. The MW of Na3AsO4 is 207.862 g/mol and for H3AsO4, pKa1 = 2.24, pKa2 = 6.96, and pKa3 = 11.50.

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1 pka and ph problem
Calculate the mass (g) of pure Na3AsO4 (s) and volume (mL) of 1.50 M HCl that are required to make 100.0 mL of a buffer solution at a pH of 6.80 and an H2AsO4-(aq) concentration of 0.100 ...

#### Solution Summary

This solution explains how to determine the mass of a weak acid salt needed to create a buffer solution with a specific concentration of weak acid at a specific pH. The weak acid in question is arsenic acid.

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