0.397g/204=0.00194608mol this is the moles of the potassium hydrogen phthalate. Assuming the reaction ratio is 1:1 this is the same number of moles for the sodium hydroxide. we now use the solution triangle rearranged to find concentration. Moles/volume=concentration
0.00194608mol/16.22ml/1000(to convert to decimeters cubed)
Final answer is 0.00000012M-1.2x10-7
