(a) Sodium acetate, CH3COONA was hydrolysed in water, H2O. Show the reaction equations involved. What is the effect of the salt on the pH of this solution? (b) (i) Define buffer solution. (ii) 2.50 g of sodium acetate, CH3COONa was dissolved in 150.0 mL of water, H2O. A solution of 0.025 M ethanoic acid, CH3COOH was added into the above salt solution. Calculate the pH of the mixed solution. [pKa of CH3COOH = 4.75, Molar mass of CH3COONA = 82.0 g mol-1] %3D

(a) Sodium acetate, CH3COONA was hydrolysed in water, H2O. Show the reaction equations involved. What is the effect of the salt on the pH of this solution? (b) (i) Define buffer solution. (ii) 2.50 g of sodium acetate, CH3COONa was dissolved in 150.0 mL of water, H2O. A solution of 0.025 M ethanoic acid, CH3COOH was added into the above salt solution. Calculate the pH of the mixed solution. [pKa of CH3COOH = 4.75, Molar mass of CH3COONA = 82.0 g mol-1] %3D

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 49P

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9. A buffer solution is made of 6.1 g of benzoic acid (C6H5COOH) and 0.60 g of sodium benzoate (C6H5COONa) in exactly 500 cm³ of solution I (a) What is the pH of the buffer? (b) If the solution is diluted to exactly 1 litre with pure water, what is the new pH of the solution? (c) Write a chemical equation to show what happens when NaOH is added to this buffer. (d) Calculate the pH of 85 cm³ of buffer after 0.80 g of NaOH is added to it. Assume no volume change.
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