A 2.5 g sample of NaOH (Mw = 40.00) was dissolved in water to give a

Question

solution of final volume 250 cm3.
(i) With reasons, state whether NaOH is a strong or a weak base. Give the
conjugate acid of NaOH and decide whether this conjugate acid is acid,
alkaline or neutral.
(ii) Calculate the molarity NaOH in the solution.
(iii) Calculate the pH of the solution.
(iv) Calculate the molarity of the resulting solution if 100 cm3 of water is
added to the original 250 cm3 NaOH solution. Find the pH of the new
solution.
(v) 4.5 g of acid HA (Mw = 60.00, pKa = 4.8) is added to 100 cm3 of the
original NaOH solution. Assuming no dilution occurs; calculate the pH
of the resulting solution.