Uppose you perform a titration of an unknown weak acid solution. You start with 4.00 mL of the weak acid and find that it takes 12.8 mL of 0.0500 M NaOH to reach the equivalence point. What is the concentration of the unknown weak acid solution?

Explanation:

It is known that at the equivalence point,

     Equivalent of acid = equivalent of base ......... (A)

and,     Equivalent =

Therefore, equivalent of acid is calculated as follows.

     Equivalent of acid = .......... (1)

     Equivalent of base = ............ (2)

Hence, using equation (A) we will calculate the concentration as follows.

                       M = 0.16 M

Thus, we can conclude that concentration of the unknown weak acid solution 0.16 M.                    

it means there are 3 atoms of oxygen