
Jade H. answered 11/01/16
Tutor
New to Wyzant
PhD Chemist for Math and Chemistry Tutoring
HCl + NaOH --> H2O + Na+ + Cl-
So we can use the 1:1 mole ratio to calculate the volume of the 0.0321 M NaOH needed to neutralize the solution.
Calculate the moles of HCl: (0.0399 mol/L)(0.025L) = 9.975 x 10-4 mol HCl
Because its a 1:1 ratio the moles of HCl are equal to the moles of NaOH at the endpoint (neutralized solution), so we can then find the volume (V) of the NaOH solution
0.0321 M = 0.0321 mol/L = 9.975 x 10-4 mol/V
V = 9.975 x 10-4 mol/(0.0321 mol/L) --> V will be in liters