Acid-Base Titration Lab Report

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

When using different methods to measure pH levels there are some tools that can be useful. Some more than others but by putting into action the different methods it may determine which tools will work best and give the best results when testing the pH within a solution. The pH, which stands for the proportion of hydrogen ions in a solution, could be acidic (acidosis), neutral or basic (alkaline). The pH scale goes from numbers 1 through 14. A pH of 7 is neutral;

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.

In order to test the rate of phagocytosis in tetrahymena, the tetrahymena need to ingest particles that are visible under a light microscope. The substance used in this experiment was India ink. India ink is deep black colored ink containing dispersed carbon particles. The trethymena treat the India ink as if it were food and ingest it. There were three concentrations of India ink that were fed to the eukaryotes The percent’s that were used are: 1%, 5% and 10% of India ink. After certain time intervals, the tetrahymena were fixed with a compound called 3% paraformaldehyde (PFA).On the first day six different mixtures of tetrahymena and ink concentrations were made to test which conditions would express the best rate of phagocytosis. The well fed tetrahymena were fed with 1% India ink, the another group was fed 5% India ink, the last group was fed 10% India ink. Then the starved tetrahymena were fed in the same manner as the well-fed tetrahymena. After adding the ink to the microcentrifuge, we prepared a slide for each mixture at the following time intervals 2 minutes, 5 minutes, 10 minutes, 20

2. (5 pts) List and explain the names and affiliations of the various characters/stakeholders in this story – I’m looking for us to use the story to map out the complexities that are generally associated with solving public health puzzles – the stakeholders you list and explain here should apply to many of the cases we consider going forward.

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

Acid-base reactions reach the equivalence point when an equal number of moles of acid react with the base. As soon as we see a change in color of the solution, the reaction is complete and the titration can be stopped. The change in color are due to the indicator.

The lab’s purpose is to standardize a prepared sodium hydroxide solution and use it to determine the molarity of an unknown acid. Moreover, acids and bases react with the known stoichiometric ratios based on the coefficients of the balanced chemical reactions. If the stoichiometric ratio of an acid-base reaction is known the unknown concentration can be determined, however the reaction must have gone through completion and the number of moles of one of the components needs to known. The pH scale can be used to determine the change in concentration of an acid or base. The pH scale is calculated through the formula (pH = -log[H+]). Furthermore, when an acidic compound interacts with basic compound, the concentration of hydrogen decreases, therefore

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

Finally, we were then able to solve for the initial concentration of NaOH in each titration by converting the 20.0 mL NaOH solution used from mL to L, and then plugging it into the molarity equation along with the mols of NaOH we determined. The initial concentration of NaOH was found to be 0.0780M in titration 1, 0.0739M in titration 2, and 0.0745M in titration 3. The average concentration of NaOH was then determined by adding up the initial concentrations of titration 1, 2, and 3 and then dividing the sum by 3. The average concentration of NaOH was calculated to be 0.0755

At that point, the pH begins to rapidly change until there is no more acid to react: this is when the reaction reaches the equivalence point. To designate when this equivalence point occurs, the indicator, Phenolphthalein was used. However, this was not the desired point, for one needed to equate the pH to the pKa. By adding an equal amount of weak acid solution – as compared to the starting solution – in the overall solution, one was able to equate the moles of conjugate base with the moles of conjugate acid. This point

The purpose of this experiment was to determine how much KMnO4 was needed to titrate approximately 1 mL of an Unknow X101 concentrated solution of Oxalic Acid. A standardized KMnO4 solution was used on a known solution of Oxalic acid to help determine the unknown percent oxalic acid in unknown X101. The unknown sample for this experiment was sample x101 which theoretically was a % Oxalic Acid dehydrate sample but, the average of all three trials determined it to be a 6.7% percent Oxalic acid.

In this lab a acid-base indicator phenolphthalein was used to determine endpoint of a reaction HCl(aq) and KOH(aq). At the end point all of the HCl(aq) would have reacted with KOH(aq), and the pH becomes 7. The phenolphthalein would changed colours from colourless to pink indication when enough KOH(aq) was added. The purpose of numerous trials was to use the average volume of the 3 trials with similar measurements.

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