Lactic acid, HC3H5O3, is the acid, which forms when milk sours. As its formula indicates, this acid has an acid hydrogen ion. It requires 22.4 mL of NaOH at 0.156 M to neutralize the acid in a sample of 25.0 mL of lactic acid. Calculate the mass of lactic acid contained in the sample.
C3H6O3 + NaOH = H2O + NaC3H5O3
Volume of NaOH =22.4 mL=0.0224L
Number of moles of NaOH =0.156M
Volume of C3H6O3=25.0mL =0. 025L
Number of moles of C3H6O3= 1mol/1mol x 0.156 x 0.0224
= 0.0034944 mole