Determine the mass of solid NaCH3COO that must be dissolved in an existing 500.0 mL solution of 0.200 M CH3COOH to form a buffer with a pH equal to 5.00. The value of Ka for CH-CООH is 1.8 х 10-5. 1 2 Let x represent the original concentration of CH;COO in the water. Based on the given values, set up the ICE table in order to determine the unknown. CH3COOH+ H2O(1) =H3O*(aq) +CH3COO-(a Initial (M) Change (M) Equilibrium (M) 5 RESET 0.200 5.00 -5.00 1.0 × 10-9 -1.0 x 10-9 1.0 x 10-5 -1.0 × 10-5 1.8 x 10-5 -1.8 x 10-5 x + 5.00 x - 5.00 x + 1.0 × 10-9 х - 1.0 x 10-9 x + 1.0 × 10-5 х- 1.0 x 10-5 x + 1.8 × 10-5 х - 1.8 х 10-5

Determine the mass of solid NaCH3COO that must be dissolved in an existing 500.0 mL solution of 0.200 M CH3COOH to form a buffer with a pH equal to 5.00. The value of Ka for CH-CООH is 1.8 х 10-5. 1 2 Let x represent the original concentration of CH;COO in the water. Based on the given values, set up the ICE table in order to determine the unknown. CH3COOH+ H2O(1) =H3O*(aq) +CH3COO-(a Initial (M) Change (M) Equilibrium (M) 5 RESET 0.200 5.00 -5.00 1.0 × 10-9 -1.0 x 10-9 1.0 x 10-5 -1.0 × 10-5 1.8 x 10-5 -1.8 x 10-5 x + 5.00 x - 5.00 x + 1.0 × 10-9 х - 1.0 x 10-9 x + 1.0 × 10-5 х- 1.0 x 10-5 x + 1.8 × 10-5 х - 1.8 х 10-5

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter13: Acids And Bases

Section: Chapter Questions

Problem 58QAP: Consider citric acid, H3C6H5O7, added to many soft drinks. The equilibrium constants for its...

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Acrylic acid is used in the polymer industry in the production of acrylates. Its K, is 5.6 X 10“’. What is the pH of a 0.11 M solution of acrylic acid, CH2CHCOOH?
8-55 We commonly refer to a buffer as consisting of approximately equal molar amounts of a weak acid and its conjugate base—for example, CH3COOH and CH3COO-. Is it also possible to have a buffer consisting of approximately equal molar amounts of a weak base and its conjugate acid? Explain.
Sketch two pH curves, one for the titration of a weak acid with a strong base and one for a strong acid with a strong base. How are they similar? How are they different? Account for the similarities and the differences.
A 10.00-g sample of the ionic compound NaA, where A is the anion of a weak acid, was dissolved in enough water to make 100.0 mL of solution and was then titrated with 0.100 M HCl. After 500.0 mL HCl was added, the pH was 5.00. The experimenter found that 1.00 L of 0.100 M HCl was required to reach the stoichiometric point of the titration. a. What is the molar mass of NaA? b. Calculate the pH of the solution at the stoichiometric point of the titration.
Consider citric acid, H3C6H5O7, added to many soft drinks. The equilibrium constants for its step-wise ionization areKa1=7.5104 ,Ka2=1.7105, andKa3=4.0107. Write the overall net ionic equation and calculate K for the complete ionization of citric acid.
Amino acids are an important group of compounds. At low pH, both the carboxylic acid group (CO2H) and the amine group (NHR) are protonated. However, as the pH of the solution increases (say, by adding base), the carboxylic acid proton is removed, usually at a pH between 2 and 3. In a middle range of pHs, therefore, the amine group is protonated, but the carboxylic acid group has lost the proton. (This is called a zwitterion.) At more basic pH values, the amine proton is dissociated. What is the pH of a 0.20 M solution of alanine hydrochloride, [NH3CHCH3CO2H]Cl?
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If the pH of a buffer solution is equal to the pKa of the acidin the buffer, what does this tell you about the relative concentrationsof the acid and conjugate base forms of the buffercomponents?(a) The acid concentration must be zero. (b) The base concentrationmust be zero. (c) The acid and base concentrations must be equal. (d) The acid and base concentrations must be equal tothe Ka. (e) The base concentration must be 2.3 times as large asthe acid concentration.
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