Question

Titration of the carbonate buffer system lab

1. How would you expect buffer capacities to change if larger masses of sodium carbonate and sodium bicarbonate were used in each titration?

2. How would you expect the buffer capacities to change if a more concentrated solution of HCl was used in the titration?

Answer 1

Solution:

1) If larger masses of sodium carbonate and sodium bicabonate are used, then it will increase the buffer capacity. The buffer capacity of a buffer is represented by β as,

β = ΔA / ΔpH

Thus, large masses of sodium carbonate and sodium bicarbonate causes to minimizes the change in pH. Thus, it will increase the buffer capacity.

2) If more concentrated solution of HCl is added, then it will causes to decrease the pH. Thus, the value of change in pH (ΔpH) is large. Therefore, buffer capacity will decreases.

β = ΔA. /ΔpH