Question

What is the concentration (in moles per liter) of a hydrochloric acid (HCl) solution if 25 mL of the solution reacts with 50 mL of a 0.1 M sodium hydroxide (NaOH) solution during a titration process?

Answer 1

To find the concentration of the hydrochloric acid solution, we can use the concept of stoichiometry and the balanced chemical equation for the reaction between HCl and NaOH:HCl  aq  + NaOH  aq   NaCl  aq  + H2O  l From the balanced equation, we can see that 1 mole of HCl reacts with 1 mole of NaOH.First, we need to find the moles of NaOH in the 50 mL of 0.1 M solution:moles of NaOH = volume  L   concentration  M moles of NaOH = 0.050 L  0.1 mol/Lmoles of NaOH = 0.005 molSince the mole ratio of HCl to NaOH is 1:1, the moles of HCl that reacted with NaOH are also 0.005 mol.Now, we can find the concentration of the HCl solution using the moles of HCl and the volume of the HCl solution:concentration  M  = moles of HCl / volume  L The volume of the HCl solution is given as 25 mL, which is equal to 0.025 L. So,concentration  M  = 0.005 mol / 0.025 Lconcentration  M  = 0.2 MTherefore, the concentration of the hydrochloric acid solution is 0.2 moles per liter.