Determine the concentration of the acid

Question

The flask contains 25mL of an unknown diprotic acid aqueous solution that reacts in a 1:2 stochiometric ratio with NaOH. Tritrate the solution with NaOH to determine the concentration of the acid.

Answer 1

Unfortunately, there isn't enough info to solve this problem! For acid/base titrations, we need concentrations and volumes of each solution with up to one unknown. For this case, we can set (moles of acid) = 2(moles of base) because the acid is diprotic, shedding two protons per mole of acid.

moles of acid = concentration of acid * volume of acid

moles of base = concentration of base * volume of base

concentration of acid * volume of acid = 2 * concentration of base * volume of base

(M_aV_a) = 2(M_bV_b)

We have an unknown volume and concentration of NaOH and an unknown concentration of our diprotic acid, so we can't solve the equality.