Titration : An Acid Base Titration

1. To titrate a hydrochloric acid solution of “unknown” concentration with standardized 0.5M sodium hydroxide.

9) Filter the ppt formed as result of step 7 from the newly acidic solution.

pH was recorded every time 1.00 mL of NaOH was added to beaker. When the amount of NaOH added to the beaker was about 5.00 mL away from the expected end point, NaOH was added very slowly. Approximately 0.20 mL of NaOH was added until the pH made a jump. The pH was recorded until it reached ~12. This was repeated two more times. The pKa of each trial are determined using the graphs made on excel.

In this assignment you will be asked to rank aqueous solutions of acids, bases, and salts in order of increasing pH. This is most easily done by first identifying the strong acids that have the lowest pH, the strong bases that have the highest pH, and the neutral solutions that have a pH near 7. The weak acids

A patient with poorly controlled Type I diabetes has blood drawn and finds that the pH of his blood is 7.1. The normal pH of blood is 7.4. The patient's blood [H+] is

To start out this study the difference between acids and bases has to be identified. Acids have very low pHs and have a high concentration of hydronium ions, while bases have a high pH and have a high concentration of hydroxide ions. The difference between strong bases and acids, and weak bases and acids is the amount of dissociation. Strong bases and acids dissociate a large amount and let go of their ions in solution, while weak bases and acids may only let go of some of their ions. This is important because if the unknown solutions aren’t strong acids or bases then using their ions to calculate the pH of the solutions will give false results (Diffen 2012).

1. Describe the graph of pH values over the course of the reaction in Part II. Was the change in pH consistent over the course of the reaction? Do your best to explain the reason for the shape of the pH curve in your own words:

Question: The equivalence points of the two titration curves were not in the same pH range. Explain. (Why was the pH at the equivalence point different for the two different acids?)

To improve the results from the experiment buffer solutions that were not whole pHs could have been used e.g. pH 4.5, 5.5 etc. This would have provided more reliable results as a wider range of results would have been produced. Using pHs with decimals would also help to more accurately determine the optimum pH as the optimum may have been above or below the pH stated in the hypothesis; 8. In this experiment however the optimum is taken at 8 because the graph does not rise again.

2. In Part I of this experiment, acetic acid is titrated with NaOH. The net ionic equation for acetic acid reacting with NaOH is CH3COOH+ NaOH =NaC2H3O2+H2O. The equivalence point is when the moles of the titrant and other solution are equal.. You detect the equivalence point by obtaining the point on the graph where the steep pH occurs. In titrating acetic acid with NaOH, the pH is greater than 7 at the equivalence point because NaOH is a strong base so it results in a higher pH, due to the OH- ions in the solution.

During a titration the pH of the solution will be monitored using a pH meter from that we get a titration curve. The titration curve is then used to determine the equivalent molecular weight and Ka value of the unknown weak acid, from that we are

Using Graph 1: The Volume of Titrant Added in order to reach the Endpoint and the Corresponding pH Values, observe the vertical line of each titration and see the points in which the horizontal lines intersect it. These points give the

First, three titration curves and three second derivative curves were created to determine the average pH at the half-equivalence point from the acetic acid titrations. Titration curves were used as visuals to portray buffer capacity. The graphs and a table, Table 1, that showcased the values collected were created and included below. The flat region, the middle part, of Figures 1, 2 and 3, showed the zone at which the addition of a base or acid did not cause changes in pH. Once surpassed, the pH increased rapidly when a small amount of base, NaOH, was added to the buffer solution. Using the figures below and

2. Following solutions are added to the tubes and the pH of each tube is determined:

An acid-base titration is the determination of the concentration of an acid or base by exactly neutralizing the acid/base with an acid or base of known concentration. This allows for quantitative analysis of the concentration of an unknown acid