SALT HYDROLYSIS

Question

1.) Calculate the pH of a 0.24M sodium formate (HCOONa) solution. Kb=5.9x10^-11.
2.) Calculate the pH of 0.25M pyridium chloride (C5H5NHCl)solution. Ka=5.9x10^6.

Answer 1

1.) The pH of a 0.24M sodium formate solution can be calculated using the Henderson-Hasselbalch equation:

pH = pKa + log([salt]/[acid])

pKa = -log(Kb) = -log(5.9x10^-11) = 10.22

pH = 10.22 + log(0.24/0.24) = 10.22

2.) The pH of a 0.25M pyridium chloride solution can be calculated using the Henderson-Hasselbalch equation:

pH = pKa + log([salt]/[acid])

pKa = -log(Ka) = -log(5.9x10^6) = 6.23

pH = 6.23 + log(0.25/0.25) = 6.23