Statement I : In the titration of Na₂CO₃ with HCl using methyl orange indicator, the volume of the acid required at the equivalence point is twice that of the acid required using phenolphthalein as indicator.

Statement II : Two moles of HCl are required for the complete neutralization of one mole of Na₂CO₃.

In presence of phenopthalein, only strong bases are neutralised and color chnage is observed as if changes color in the range 8.2 to 10.

In presence of methyl orange whose color range of P^H is 3.3 to 4.4, both strong and wek bases are neutralised.

In other words, in presence of phenopthalein half the equivalents of Na₂CO₃ is neutralised while in presence of methyl orange complete equivalents of Na₂CO₃ is neutralised.

CO₃^-2 is a stronger base than HCO₃^-