3. Lactic acid , HC3H5O3 , is a monoprotic acid that dissociates in aqueous solution, as represented by the equation(not given).
Lactic acid is 1.66 % dissociated in 0.50M HC3H5O3. (aq) at 298K.
A) Write the expression for the acid- dissociation constant , Ka , for lactic acid and calculate its value.
B) Calculate the pH of 0.50M HC3H5O3.
C) Calculate the pH of a solution formed by dissolving 0.045 mole of sodium lactate, NaC3H5O3 in 250ml of 0.50M HC3H5O3. Assume that volume change is negligible.
D) A 100ml sample of 0.10 M HCL is added to 100ml of 0.50M lactic acid. Calculate the Molar concentration of the lactate ion C3H5O3- , in the resulting solution.