A beaker contains a 25 mL solution of an unknown monoprotic acid that reacts in a 1:1 stochiometric ratio with NaOH. Titrate the solution with NaOH to determine the concentration of the acid. Perform a titration by setting the concentration of the NaOH solution and adding it to the acid solution using the different Add Base buttons. The equivalence point of the titration is passed when the solution color changes. The unknown sample can be titrated multiple times by pressing the Retitrate button and starting over. Enter the concentration of the unknown acid solution.