40g NaOH, 106g `Na_(2)CO_(3)` and 84g `NaHCO_(3)` is dissolved in water and the solution is made 1 litre. 20 mL of this stock solution is titrated with 1N HCl, hence which of the following statements is/are correct?

Options

A. The litre reading of `HCI` will be 40mL, if phenolphthalein is used indicator from the very beginning
B. The litre reading of HCI will be 60mL if phenolphthalein is used indicator from the very beginning
C. The litre reading of HCI will be `40mL` if the methyl orange is used indicaor after the `1^(st)` end point
D. The tire reading HCI will be `80mL` if methyl orange is used as indicator from the very beginning

Answer

A, D

Explanation

With Hph:
m.eqts of acid = m.eqts of `NaOH +1//2` m.eqts of `Na_(2)CO_(3)`
After Ist end point, using methyl orange,
m.eqts of acid = m.eqts of `NaHCO_(3) +1//2`
m.eqts of `Na_(2)CO_(3)`