Asolution of hcooh has 0.22m hcooh at equilibrium. the ka for hcooh is 1.8×10−4. what is the ph of this solution at equilibrium?

Answer : The pH of the solution is, 2.21

Solution :  Given,

Concentration (c) = 0.22 M

Acid dissociation constant =

The equilibrium reaction for dissociation of (weak acid) is,

initially conc.         c                       0         0

At eqm.                                      

First we have to calculate the concentration of value of dissociation constant .

Formula used :

Now put all the given values in this formula ,we get the value of dissociation constant .

By solving the terms, we get

Now we have to calculate the concentration of hydrogen ion.

Now we have to calculate the pH.

Therefore, the pH of the solution is, 2.21