Data Analysis:

Calculations:

The number of moles of NaOH needed to reach the equivalence point for each trial:

Trial 1:  

Trial 2: 

Trial 3: 

The number of moles of HCl is the same number of moles of NaOH because the stoichiometric ratio is 1:1.

The concentration of the HCl solution:

Trial 1:

Trial 2:

Trial 3:

Average concentration of the HCl solution (M):

Conclusion:

The purpose of this lab is to determine the molar concentration of a strong acid solution by titrating measured volumes with a strong base of known concentration. This was done by using titration to determine the volume needed to find the equivalence point between the unknown concentration of the acidic HCl solution, and the known concentration of the basic NaOH solution. The concentration of NaOH was determined last lab, and it came out to be 0.9934 M. Once there is a jump in the pH during the titration, the equivalence point was reached. The stoichiometric ratio between HCl and NaOH, and volume of HCl needed to reach the equivalence point can be used to determine the concentration of the HCl solution.

After doing the calculations the concentration of the HCl solution is 0.0694 M. The concentration was suppose to be 0.1 M, so it was not very accurate.  Some sources of  errors that could of occurred during the experiment were making the HCl solution inaccurately, not calibrating the pH sensor correctly, or making some sort of error when making the NaOH solution during the previous lab. In the future, the experimenters should be more careful when making the solutions, calibrating the pH sensor correctly, and making sure everything in the set up is working properly including the titrator.