Question

a 0.200 mol/L acetic acid solution and of a 0.100 mol/L sodium acetate solution, sufficient to prepare a liter of buffer. Based on this problem, determine by showing your calculations: a) The pH of this buffer;

Answer 1

Buffer solution pH

Acetic acid: Ka = 1,76 x 10⁻⁵

pKa = - log Ka = - log 1,76 x 10⁻⁵ = 4,75

pH = pKa + (log [acetate] / log [acetic acid])

pH = 4,75 + (log 0,1 / log 0,2)

pH = 4,75 + (- 1 / - 0,7)

pH = 4,75 + 0,14

pH = 4,89