Macmillan Learning Question 7 of 20 > Attempt 1 To a 25.00 mL volumetric flask, a lab technician adds a 0.125 g sample of a weak monoprotic acid, HA, and dilutes to the mark with distilled water. The technician then titrates this weak acid solution with 0.0866 M KOH. She reaches the endpoint after adding 47.47 mL of the KOH solution. Determine the number of moles of the weak acid in the solution. moles of weak acid: 0.00369441 Incorrect Answer Determine the molar mass of the weak acid. 33.8359 molar mass= Incorrect Answer mol g/mol After the technician adds 17.39 ml. of the KOH solution, the pH of the mixture is 5.33. Determine the pKa of the weak acid. 4.68858 PK₁ = Incorrect Answer

Macmillan Learning Question 7 of 20 > Attempt 1 To a 25.00 mL volumetric flask, a lab technician adds a 0.125 g sample of a weak monoprotic acid, HA, and dilutes to the mark with distilled water. The technician then titrates this weak acid solution with 0.0866 M KOH. She reaches the endpoint after adding 47.47 mL of the KOH solution. Determine the number of moles of the weak acid in the solution. moles of weak acid: 0.00369441 Incorrect Answer Determine the molar mass of the weak acid. 33.8359 molar mass= Incorrect Answer mol g/mol After the technician adds 17.39 ml. of the KOH solution, the pH of the mixture is 5.33. Determine the pKa of the weak acid. 4.68858 PK₁ = Incorrect Answer

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.17QAP

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Chem. 1A: Acid-Base titration : to determine molar mass of a diprotic ACID : H2A Put a weighing paper on the pan of balance and tare it. Then add 0.1482 g of an unknown diprotic acid. Transfer the acid to a Erlenmeyer flask add 35.0 mL. water and 4 drops phenophethaleine. The color of solution is colorless. Set up a 50.00 mL. buret: wash the buret with tap water twice, with deionized water twice and and the 0.1029 M NAOH(aq). Fill the buret with 0.1029 M NaOH(aq), remove the air bubble and adjust the initial buret reading to 0.00 mL. Put the Erlenmeyer flask containing the acid and the phenolphethaleine below the buret with 0.1029 M NAOH(aq). Add NaOH(aq) from buret to the Erlenmeyer flask containing the diprotic acid and phenolphethaleine , until the color of the solution turn to pink by adding one or two drops of NaOH(aq). Then stop adding NaOH(aq) from buret and read the final volume of NaOH(aq). Acid-base titration: buret base of known concentration + stopcock acid of unknown…
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