Question 30Acetylsalicylic acid is a pain relief medication also known as aspirin. The purityof an aspirin tablet was determined by titration against a basic standard.First, the basic solution was standardised by titrating it with a standard solutionof potassium hydrogen phthalate:KHC&H4O4(aq) + NaOH(aq) → H½O(1) + NaKCsH404(aq)An average titre of 19.25 mL of the sodium hydroxide solution was required toreach equivalence with 25.0 mL of 0.0116 M potassium hydrogen phthalate.One aspirin tablet was weighed and found to have a mass of 0.370 g.It was dissolved in deionised water and made up to 250.0 mL in a volumetricflask.The standardised NaOH solution was titrated against 25.0 mL of the aspirinsolution:C9H$O4(aq) + NaOH(aq) → H2O() + NaC»H7O4(aq)The average titre of NaOH that neutralised the aspirin solution was 13.20 mL.(a) Explain why dissolving a precisely known mass of solid NaOH and makingthe solution up250.0 mL in a volumetric flask is not an appropriate wayto prepare a standard solution.(b) Identify the most appropriate piece of equipment for collecting precisely25.0 mL of the dissolved tablet solution.Question 30 continuesQuestion 30 (continued)(c) Calculate the concentration of the standardised NaOH solution.(d)Given that the molecular mass of aspirin is 180.158 g mol1, calculate thepurity of the tablet as %w/w.

Volumetric flask is used for preparing a fixed volume of solution. Like for preparing 250 ml…

(a) Explain why dissolving a precisely known mass of solid NaOH and making the solution up to 250.0 mL in a volumetric flask is not an appropriate way to prepare a standard solution. (b) Identify the most appropriate piece of equipment for collecting precisely 25.0 mL of the dissolved tablet solution. Question 30 continues Question 30 (continued) (c) Calculate the concentration of the standardised NaOH solution.

(a) Explain why dissolving a precisely known mass of solid NaOH and making the solution up to 250.0 mL in a volumetric flask is not an appropriate way to prepare a standard solution. (b) Identify the most appropriate piece of equipment for collecting precisely 25.0 mL of the dissolved tablet solution. Question 30 continues Question 30 (continued) (c) Calculate the concentration of the standardised NaOH solution.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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