Question

A procedure has 250 mM pH = 5 acetate buffer. 1) What concentrations of acetic acid and sodium acetate should you use? 2) If the procedure calls for 4 L of the mentioned buffer solution, how many grams and moles of each buffer component will be needed?

Answer 1

(1) Let the concentration of acetic acid be x M.
Total concentration of acetic acid and acetate ion is 250 mM or 0.250 M.
The concentration of acetate ions will be M
For acetic acid,

Hence, the concentration of acetic acid is 0.0887 M or 88.7 mM and the concentration of acetate ion is M or 161 mM

(2)
For 4 L of buffer solution, the number of moles of acetic acid required are mol
The molar mass of acetic acid is 60 g/mol.
The mass of acetic acid is g

For 4 L of buffer solution, the number of moles of acetate ions required are mol
The molar mass of acetate ion is 59 g/mol.
The mass of acetate ion is