Question

Calculate the ph of a solution that is 0.278 m in sodium formate (nahco2) and 0.222 m in formic acid (hco2h). the ka of formic acid is 1.77 × 10^-4.

Answer 1

Use the formula:

pH = pKa + log[Conjugate base] / [Acid]

      =  -log(1.77 × 10^-4)  + log[0.278] / [0.222]

     =   3.75 + 0.097
     = 3.84