orgo lab 1 - Organic Chemistry 201 Lab 1: Effect of pH on a...

Organic Chemistry 201
Lab 1: Effect of pH on a Food Preservative
Introduction: In this lab, the effect of pH on food preservative was observed using sodium benzoate and
hydrochloric acid. As the sodium becomes and ion in the solution, the benzoate acquires a proton from
the hydrochloric acid, forming a precipitate of benzoic acid. This precipitate was vacuum filtrated to
isolate the solid white product. We also conducted a second experiment where the volume and mass of
an unknown that was measured in order to find its density.
Data/Calculations:
Mass of Sodium Benzoate .401g
Volume of water 3.0ml
Volume of 3M HCl 1 ml
Actual yield .468g
Theoretical yield (Benzoic Acid) .34g
Percent yield 137.6
%
Experimental Procedure: All procedures for these experiments were followed as they were given in the
lab manual.
Discussion: In the first experiment, sodium benzoate and hydrochloric acid were mixed to form a
precipitate of benzoic acid. When sodium benzoate is reacted with hydrochloric acid and water, the