In the reaction h2so4 + 2 naoh -> na2so4 + 2h2o, an equivalence point occurs when 18.45 ml of 0.1953 m naoh is added to a 21.25 ml portion of h2so4. what is the [h2so4]?

The solution is found using chemistry techniques.
            moles NaOH = c · V = 0.1953 mmol/mL · 18.45 mL = 3.603285 mmol
            moles H2SO4 = 3.603285 mmol NaOH · 1 mmol H2SO4 / 2 mmol NaOH = 1.8016425 mmol
Hence
            [H2SO4]= n/V = 1.8016425 mmol / 21.25 mL = 0.08478 M
The answer to this question is  [H2SO4] = 0.08478 M