Question

What is the concentration of a hydrochloric acid solution if 25.00 mL of it requires 34.87 mL of a 0.120 M sodium hydroxide solution to reach a neutral pH during titration?

Answer 1

To find the concentration of the hydrochloric acid solution, we can use the concept of titration and the balanced chemical equation:HCl  aq  + NaOH  aq   NaCl  aq  + H2O  l From the balanced equation, we can see that the mole ratio of HCl to NaOH is 1:1.First, we need to find the moles of NaOH used in the titration:moles of NaOH = volume of NaOH  L   concentration of NaOH  M moles of NaOH = 0.03487 L  0.120 Mmoles of NaOH = 0.0041844 molSince the mole ratio of HCl to NaOH is 1:1, the moles of HCl will be equal to the moles of NaOH:moles of HCl = 0.0041844 molNow, we can find the concentration of the HCl solution:concentration of HCl  M  = moles of HCl / volume of HCl  L concentration of HCl  M  = 0.0041844 mol / 0.02500 Lconcentration of HCl  M  = 0.167376 MTherefore, the concentration of the hydrochloric acid solution is approximately 0.167 M.