Titrations of a strong acid or base with a weak acid or base yield results that greatly differ then a strong-strong titration. The strong-weak titrations allow for an in depth analysis of the half-equivalence point as well as buffers. The half equivalence point allows the calculation of pH from pKa, as they are both equal at the half equivalence point, proven by the Henderson Hasslbach equation. It was Henderson in 1908 that created an equation allowing for the logarithmic calculation for pH from a buffer and the pKa which consequently lead to the knowledge and applications of buffers that we have today. Buffers were also analyzed in the experiment as buffers consist of equal molar rations of a weak acid and its conjugate base, which then
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First, a buffered solution of acetic acid and sodium acetate was made by combing 15 mL of .5 M acetic acid, 15 mL of deionized water, and 1.020 grams of sodium acetate. A solution of .25 M NaOH was then prepared using 25 mL of .5 Ml NaOH and 25 mL of deionized water. The burette was then conditioned with 10 mL of deionized water twice and twice with 5 mL of .5 M NaOH. The burette was then filled with .25 M NaOH and the initial volume of 25 mL was recorded. A volumetric pipette was then used to add 10 mL of acetic acid to 50 mL of deionized water and the beaker was placed below the burette. The pH probe was then rinsed and placed in the acetic acid buffer solution and an initial pH reading was taken. The titration was then started by adding NaOH in .5 mL increments until the pH changed dramatically. Once the buffering capacity was –assed six .5 mL portions of NaOH were added. The data collection was then stopped and all waste was disposed of properly and the pH probe was rinsed and placed in deionized …show more content…
A solution of .25 M HCl was first prepared by placing 25 mL of .5 M HCl in 25 mL of deionized water. The burette was then reconditioned with two 10 mL portions of deionized water and tow 5 mL portions of HCl. The burette was then filled to the 25 mL mark. A volumetric pipette was then sued to transfer 10 mL of acetic acid buffer to 50 mL of deionized water and the beaker was then placed below the burette. The pH probe was then rinsed and placed in the buffer solution to obtain an original pH reading. The titration was done in .5 mL increments until the pH of the solution changed dramatically while recording ach volume and pH. Once the buffering capacity was passed six .5 mL portions of HCl were added and recorded. The data collection was then stopped and all waste was disposed of properly. All data from the Lab Quest was then saved onto a USB drive. The pH probe was rinsed of and placed back in tis container, unplugged and returned to its proper storage place. The Lab Quest was turned off and put away. All materials were cleaned with deionized water, dried, and placed in their proper storage
First, a buffered solution of acetic acid and sodium acetate was made by combing 15 mL of .5 M acetic acid, 15 mL of deionized water, and 1.020 grams of sodium acetate. A solution of .25 M NaOH was then prepared using 25 mL of .5 Ml NaOH and 25 mL of deionized water. The burette was then conditioned with 10 mL of deionized water twice and twice with 5 mL of .5 M NaOH. The burette was then filled with .25 M NaOH and the initial volume of 25 mL was recorded. A volumetric pipette was then used to add 10 mL of acetic acid to 50 mL of deionized water and the beaker was placed below the burette. The pH probe was then rinsed and placed in the acetic acid buffer solution and an initial pH reading was taken. The titration was then started by adding NaOH in .5 mL increments until the pH changed dramatically. Once the buffering capacity was –assed six .5 mL portions of NaOH were added. The data collection was then stopped and all waste was disposed of properly and the pH probe was rinsed and placed in deionized …show more content…
A solution of .25 M HCl was first prepared by placing 25 mL of .5 M HCl in 25 mL of deionized water. The burette was then reconditioned with two 10 mL portions of deionized water and tow 5 mL portions of HCl. The burette was then filled to the 25 mL mark. A volumetric pipette was then sued to transfer 10 mL of acetic acid buffer to 50 mL of deionized water and the beaker was then placed below the burette. The pH probe was then rinsed and placed in the buffer solution to obtain an original pH reading. The titration was done in .5 mL increments until the pH of the solution changed dramatically while recording ach volume and pH. Once the buffering capacity was passed six .5 mL portions of HCl were added and recorded. The data collection was then stopped and all waste was disposed of properly. All data from the Lab Quest was then saved onto a USB drive. The pH probe was rinsed of and placed back in tis container, unplugged and returned to its proper storage place. The Lab Quest was turned off and put away. All materials were cleaned with deionized water, dried, and placed in their proper storage