1) Concentration of hydrogen ions and pH of the buffer solution containing 0.15 mole of acetic acid and 0.125 mole of sodium acetate in 1 dm³ of the solution (Ka = 1.86 x 10^-5)

2) How will the concentration of hydrogen ions and the pH of this buffer change after adding 5 cm³ of HCl at a concentration of 1 mol/dm³ to it.

3) How will the concentration of hydrogen ions and the pH of this solution change if 3 cm³ of a 0.25 molar NaOH solution is added to it.

4) How will the concentration of hydrogen ions in 1 dm³ of 0.05M H₂SO₄ change if we add to it successively 1 cm³ of 1 molar HCl and 3 cm³ of 1 molar NaOH.