If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂solution is 3.74,which of the following is TRUE? A) [HCHO₂] [NaCHO₂] B) [HCHO₂] = [NaCHO₂] C) [HCHO₂]

Question

If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂solution is 3.74,which of the following is TRUE? A) [HCHO₂] > [NaCHO₂] B) [HCHO₂] = [NaCHO₂] C) [HCHO₂] < [NaCHO₂] D) [HCHO₂] < <[NaCHO₂] E) It is not possible to make a buffer of this pH from HCHO₂ and NaCHO₂.

Quizplus · Accepted Answer

At a pH equal to the pKa of the acid, the acid and its conjugate base are present in equal amounts. Therefore, in this case, [HCHO₂] = [NaCHO₂]. Choice B is the only option that reflects this relationship between the acid and its conjugate base at a pH equal to the pKa.

If the PKa of HCHO2 Is 3

If the PKa of HCHO₂ Is 3