What is the pH of a buffer?

Question

The K_a of H₂CO₃ is 4.3 x 10^-7. What is the pH of a buffer with 0.10 M H₂CO₃ and 0.010 M NaHCO₃?

Answer 1

You'll have to use the Henderson Hasselbach equation to solve this problem.

The equation is pH = pka + log (A-/Ha)

1) First convert the Ka into pka by using the equation pka = -log(Ka)

2) Determine what is A- or HA

3) Plug the values into the equation and you'll get the pH of the solution!

Hope that helped!