Effect of Buffers on pH Levels

Effect of pilot programs on pH LevelsAbstractA raw sienna is a solution that helps nutrition the pH of other solutions at a steady level with the addition of limited acids or bases. The purpose if this experiment was to figure out how to create an optimal pilot and to secure how effective relents argon at stabilizing the pH of different solutions. An optimal mince was made after calculating the H+ levels and determining how a lot weak acid and conjugate base was needed to test when added to beakers containing either acidic or basic solutions. The results found that the buffers helped get the solutions closer to a deaf(p) pH and were found to be effective pH stabilizers.IntroductionIn the real world, pH levels are important in the function of many aliveness processes. For instance, the average human bodys average pH level is approximately 7.4, and if there are any changes to that pH at all, no matter how small it may be, one would eventually get sick and die, since the hum an body is not meant to handle such a large fluctuation of pH levels. These pH levels are the measurement of Hydronium ions (H3O+) in a solution and are measured on a pH scale going from 0 to 14, with 7 being neutral, anything little than 7 would be considered acidic, and anything greater than 7 would be considered basic. One might wonder how a persons pH levels do not change so easily, and the get along is be antecedent of a solution is known as a buffer. The main function of buffers is to help keep pH levels steady when a certain amount of acids or bases are introduced in a solution. Once a buffer has reached its limit, the solution will exponentially increase or decrease, depending on if a base or an acid were used, respectively. In the graph shown, it depicts how the buffer helps to keep the pH levels steady for as long as it can, but when too much base is added, the buffer will reach its capacity and the excess base will cause the pH to rise quickly, while an addition of exce ss base will cause the pH to drop quickly. Buffers are made from weak acids or bases paired with their conjugate bases or acids, and weak acids and bases are used because they do not separate fully in a solution and the henry or hydroxide (OH) ions will mostly stay connected to the other molecules, unlike strong acids or bases that will completely dissociate into either the hydrogen or hydroxide ions. A bang-up weak acid to use is acetic acid (CH3COOH), which is commonly found in vinegar. Another thing to keep in mind is how this relates to Le Chateliers Principle, which means for acetic acid that if a base were added, the equilibrium would raise up to the right to want to produce more hydrogen ions, and if an acid were added, the equilibrium would shift left to want to produce more conjugate base. Lastly, a good buffer should have equal amounts of a weak acid and a conjugate base, which is done experimentally.Materials and MethodsMaterials usedThree 250 mL beakersOne 50 mL gra duated cylinderOne 10 mL graduated cylinderAn unknown weak acidKa=CH3COO/CH3COOHpH=-logH+H+ =10-pHKa=(H+*WA)/HWAProceduresObtain three 250 mL beakers, and a 10 mL and a 50 mL graduated cylinder.To the first beaker, add a pipette bulb of the unknown weak acid and one hundred ten mL of distilled water.Measure 50 mL of the acid solution and add it to each of the remaining two beakers, and then wash away it out and keep the beaker. enounce one beaker HWA, or acid, and the other WA, or conjugate base.Fill burette with an NaOH solution and add two to three drops of phenolphthalein indicator to WA beaker and titrate solution apply base in burette to indicator end point, which will be signaled through a ping color change, so HWA will be born-again to WA.Determine the volume of base added to WA beaker during titration and add that same volume of water to the HWA beaker so that the HWA=WA.Make an optimal buffer by mixing 20 mL of HWA and 20 mL WA in the third beaker.Prepare pH meter by st andardizing it with standard solutions of pH 4 and 7.Take pH of optimal buffer and calculate H+ from pH reading.Determine Ka value and show calculations to TA, and a refreshful buffer will be charge to be made.Using assigned buffer, determine H+.Use Ka equation to determine volume of conjugate base needed when 10 mL of acid is used, and use Ka value from step 10, H+ value from pH, and 10 mL to re perspective CH3COOH to find volume of CH3COO needed.Make a new buffer using these volumes in a clean beaker, then take the pH of the new buffer to see how close the found pH is to the assigned value.Get two 50 mL beakers and add 5 mL of new buffer to one beaker and 5 mL of distilled water to the other.Add five drops of NaOH to each beaker and read pH for each one and record both.Thoroughly wash out small beakers and repeat step 13.Add five drops of HCl to each beaker and read pH for each one and record both.Clean up and enlistment in data sheet.Results Data and Calculations0.10 M NaOH ad ded to 50 mL of acid mixtureInitial Burette readmLFinal Burette Reading34.7 mLVolume of NaOH Added16.3 mLpH of Optimal Buffer4.7Ka of Unknown Weak Acid2*10-510-4.7=2*10-5=KaAssigned pH of new buffer to make 4.85New Buffer DataH+ needed1.41*10-5Ka H+=(Ka/H+)1.42AHWA=(Ka/H+)1.42Volume of A14.2 mLVolume of HWA10 mLpH of New Buffer4.84(2*10-5)/(1.41*10-5)=1.42 strain of New BufferpH of Distilled Water with Acid2.88pH of New Buffer with Acid4.5pH of Distilled Water with Base10.9pH of New Buffer with Base5.18Discussion/ConclusionIn conclusion, the results determined that the buffer was effective at stabilizing the pH of both solutions containing distilled water and either an acid or a base added. The results also showed that the new buffer pH was very similar to the assigned pH, indicating that the overall reactions in this experiment were precise and accurate. A buffer is a solution that controls the pH of other solutions it is added in from fluctuating, and it is made by mixing equal a mounts of a weak acid with its conjugate base. The reason it necessitate to be a weak acid because it will not dissociate fully when added in a solution, so the hydrogen ions will mostly be intact and not free floating. This would be able to help the pH of the solution in which it is added stable when combined with the conjugate base that is formed when the hydrogen ion dissociates from its original molecule from which it was connected.The Ka of the weak acid used in this experiment was determined after titrating NaOH to the acid mixture until the indicator turned light pink and then taking the pH reading of the titrated solution and using the 10-pH formula to find H+ which equaled the Ka of the weak acid. The new buffer was then made when the newly assigned pH was taken, the H+ needed to achieve that new pH was determined, the Ka value by the needed H+ value was divided, and the decimal for the product was moved one decimal place to the right, since the amount of HWA needed was 10 mL, and the pH was then determined from that solution, and it matched very closely to the assigned pH. Lastly, although not major, there was one experimental error that occurred when the solutions watchful in the first part of the lab were accidentally disposed of early, but a new solution was made again which was the same pH of the antecedent solution, so that error did not affect the overall results of this experiment.