Answer:
a) pH = 4.68 (more effective)
b) pH =4.44.
Explanation:
The pH of buffer solution is obtained by Henderson Hassalbalch's equation.
The equation is:
[tex]pH =pKa +log\frac{[salt]}{[acid]}[/tex]
a) pKa of acetic acid = 4.74
[salt] = [CH₃COONa] = 1.4 M
[acid] = [CH₃COOH] = 1.6 M
[tex]pH = 4.74 + log \frac{1.4}{1.6}= 4.68[/tex]
This is more effective as there is very less difference in the concentration of salt and acid.
b) pKa of acetic acid = 4.74
[salt] = [CH₃COONa] = 0.1 M
[acid] = [CH₃COOH] = 0.2 M
[tex]pH = 4.74 + log \frac{0.1}{0.2}= 4.44[/tex]
