Lab Report On Acid Base Titration

We know that that the end point of the titration is reached when, after drop after careful drop of NaOH, the solution in the flask retains its pale pink color while swirling for about 30

The purpose of this experiment is to determine an unknown concentration of acid (hydrochloric acid) with a standard solution of a base (sodium carbonate) using titration method.

Table 2: Consists of color extract taken from a red cabbage for a natural indicator. The pH reading that was measured by using the pH meter and the result of the pH reading to determine whether the solution was acidic or basic.

Chemistry 102 is the study of kinetics – equilibrium constant. When it comes to the study of acid-base, equilibrium constant plays an important role that tells how much of the H+ ion will be released into the solution. In this lab, the method of titrimetry was performed to determine the equivalent mass and dissociation constant of an unknown weak monoprotic acid. For a monoprotic acid, it is known that pH = pKa + log (Base/Acid). When a solution has the same amount of conjugate base and bronsted lowry acid, log (Base/Acid) = 0 and pH = pKa. By recording the pH value throughout the titration process and determining the pH at half- equivalence point, the value of Ka can be easily calculated. In this experiment, the standardized NaOH solution has a concentration of 0.09834 M. The satisfactory sample size of known B was 0.2117 g. The average equivalent mass of the unknown sample was found to be 85.01 g, pKa was found to be 4.69, which was also its pH at half-equivalence point and Ka was found to be 2.0439×〖10〗^(-5). The error was 1.255% for equivalent mass and 0.11% for Ka. In other word, the experiment was very precise and accurate; the identity of the unknown sample was determined to be trans-crotonic by the method of titrimetry.

This is the point of stoichiometric equivalence, meaning the number of mols of both substances are equal. The mols used in the known solution can be found by multiplying the molarity by the volume used in titration. The molarity of the unknown solution can be found by dividing the number of mols, which is equal to the number of mols titrated in the known solution, by the volume in liters of the unknown solution. Titrating in this lab works because the one H+ ion in the KHP and HCl consumes and neutralizes the one OH¬- ion found in the NaOH. Standardization involves titrating the same solution multiple times to obtain an average molarity of the solution from the many

The purpose of this virtual lab is to observe the acid-base balance in the urinary system by how PCO2 and blood pH affect the H+ and HCO3- in the urine. The renal compensation is a mechanism that shows the kidneys manage to change pH in correct way if the respiratory system is not healthy. The kidneys are two organs that help remove wastes and extra fluids out of the body. The acid-base balance is when the blood need to keep the balance of

To determine the concentrations in both parts, the change in pH is monitored for every added amount of 0.1035 M NaOH. The pH of the solution is taken using the Orion Model 420A pH reader. The data for Figures 1-4 can be found in Appendix. B.

Its concentration was found through a quantitative and qualitative titration testing. Because HCl is acidic, a 1.07M NaOH solution was used to titrate an aqueous solution of HCl (the unknown solution). The PASCO program gave the final results shown in Figure 1. A typical titration curve can be described as starting at the initial pH of the solution, then some acid/base is added, until a sharp curve either up or down takes the pH past a neutral of 7, and towards the pH level of whatever the added acid’s/base’s pH is (Clark6). The stronger the acid or base being titrated, the faster the change occurs, which means a sharper slope of the titration graph. Also, it is important to note the equivalence point on this titration graph. At the equivalence point “the correct amount of standard solution must be added to fully react with the unknown concentration” (Xavier3). In Figure 1, this equivalence point is shown by where the sharpest slope occurs in the curve, which is seen at about a pH of 5.0

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

After measuring the pH of the analyte and the volume of NaOH added using the Vernier Lab Quest PDA, a graph of titration curve of H3PO4 vs NaOH is plotted (Figure 1). A first derivative of titration curve is plotted (Figure 2) so that the end points of the titration can be easily determined. There are two peaks on the graph; one occurs when 15.788 mL of NaOH is added; another one occurs when 29.771 mL of NaOH is added. That means the endpoints occur when 15.788 mL and 29.771 mL of NaOH is added. Therefore, the concentration of the H3PO4 at the first equivalent point is 0.03579 M, and the concentration of the H3PO4 at the second equivalent point is 0.04641 M (Equation 13). The average concentration of H3PO4 is 0.04110M (Equation 14). In the titration curve, the pKa equals to the pH value at the half equivalence point (Figure 1). The pKa1 is 2.3 and pKa2 is 4.4. Therefore, the Ka1 of the solution is 0.0047. The Ka2 of the solution is 4.0x10-5 (Equation

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

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

For this experiment, a pH meter was used so this part of the experiment began with the calibration of the pH meter with specified buffers. The buret was then filled with the standard HCl solution and a set-up for titration was prepared. 200g of the carbonate-bicarbonate solid sample was weighed and dissolved in 100 mL of distilled water. The sample solution was then transferred into a 250-ml volumetric flask and was diluted to the 250-mL mark. The flask was inverted several times for uniform mixing. A 50-mL aliquot of the sample solution was measured and placed unto a beaker. 3 drops of the phenolphthalein indicator was added to the solution in the beaker. The electrode of the pH meter was then immersed in the beaker and the solution containing the carbonate-bicarbonate mixture was titrated with the standard HCl solution to the phenolphthalein endpoint. Readings of the pH were taken at an interval of 0.5 mL addition of the titrant. After the first endpoint is obtained, 3 drops of the methyl orange was added to the same solution and was titrated with the standard acid until the formation of an orange-colored solution. Readings of the pH were also taken at 0.5 mL addition of the titrant.