The results of both reactions were not expected. Originally, there were supposed to be three jumps in pH change in both reactions with different acids. Yet, in the citric acid reaction, only the third jump in pH was visible on the graph because the first two jumps were so miniscule. On the graph of the phosphoric acid reaction, only the first two jumps in pH change were visible because the last jump in pH change was too diminutive to observe. The hydronium concentration that was calculated for the citric acid reaction was 4.027 x 10^-9 M. This concentration was similar to the hydronium concentration given in the procedure: 4.0 x 10^-7 M. The hydronium concentration was found by using the pH halfway through the jump in pH change and using logarithms to isolate the concentration. The calculated hydronium concentration in the first jump in pH change of the phosphoric acid reaction was 2.137x 10^-5 M. This calculation was not as accurate as the citric acid calculations. The given hydronium concentration of the first jump in pH change was 7.5 x 10^-3 M. This variation may be because of human error when adding the NaOH to the acid or the time gaps when recording the changes in pH. The second calculated hydronium concentration for the second jump in pH change was 1.135 x 10^-9 M. This calculation was also not accurate. The given hydronium concentration for the second jump in pH change was 6.2 x 10^-8 M. This variation could possibly be from the same errors made on the first calculation of hydronium concentration in the first jump in pH change of the phosphoric acid reaction.
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