Titration Lab Report

In the chemical reaction of hydrochloric acid, HCl, and sodium hydroxide, NaOH, the theoretical ratio is one HCL for every one NaOH. By then taking a known measurement of HCl, in this case 10mL, in addition to the phenolphthalein indicator and deionized water, and titrating it with NaOH, the amount of NaOH that causes the reaction to be complete was calculable given that we know when the reaction was complete. After calculating the moles of each substance added to complete the reaction, the experimental ratio was computed. In this case, the experimental ratio of NaOH to HCl is 1.14:1 as shown in Table 2. Overall, the titration enables the ability to find the exact amount needed for a reaction. The reaction that takes place is complete when the phenolphthalein indicator causes the solution to turn an extremely faint pink.

The lab manual states that for the titration of NaOH and HCl, a volume of 7mL of titrant should complete the reaction, however, the average for the experiment was only 6.25mL. This smaller amount of NaOH could have occurred by adding too much phenolphthalein, which would have caused the substance to turn pink sooner, rather than when the reaction was complete since phenolphthalein is a weak acid. Another example of error occurred in the titration of NaOH and H2SO4, a substantial difference appeared in the theoretical ratio of 2:1 and the experimental ratio of 2.5:1. This could have occurred by adding past the titration end point, resulting in more NaOH than necessary, thus altering the ratio. Both reactions involving Ba(OH)2, had relatively low percent errors, especially in the HCl reaction (approximately 5%) and a higher percent error with H2SO4 (approximately 20%). However, despite their percent error, they still remained consistent with the theoretical