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Question

a. Find the volume of 1.0M tartaric acid, H2C4H4O6, solution that when diluted to a total volume of 250.0ml produces a solution that is 0.050M in tartaric acid.
b. Find the mass of potassium hydrogen tartrate, KHC4H4O6, required to prepare 250.0mL of a solution that is 0.050M in hydrogen tartrate ion.

Answer 1

a.  (X ml)(1.0 M) = (250.0 ml)(0.05 M)

x = 12.5 mls needed

 

b.  Molar mass potassium hydrogen tartrate = 188.177g/mol. To prepare 0.05 M hydrogen tatrate is the same as preparing 0.05 M potassium hydrogen tartrate because KHC4H4O6 => K⁺ + HC4H4O6^-

0.05 mol/L x 0.25 L x 188.2 g/mol = 2.35 g needed