0.4 g mixture of NaOH and Na2CO3 and some inert impurities were first titrated with N10 HCl using phenolphthalein as an indicator. 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of the same HCl was required for the next end point. The weight percentage of Na2CO3 in the mixture is ______. (Rounded off to the nearest integer)

0.4 g mixture of NaOH and Na2CO3 and some inert impurities were f

1.	0.4 g mixture of NaOH and Na2CO3 and some inert impurities were first titrated with N10 HCl using phenolphthalein as an indicator. 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of the same HCl was required for the next end point. The weight percentage of Na2CO3 in the mixture is ______. (Rounded off to the nearest integer)
Answer» $0.4 g$ mixture of $N a O H$ and $N a_{2} C O_{3}$ and some inert impurities were first titrated with $\frac{N}{10} H C l$ using phenolphthalein as an indicator. $17.5 m L$ of $H C l$ was required at the end point. After this methyl orange was added and titrated. $1.5 m L$ of the same $H C l$ was required for the next end point. The weight percentage of $N a_{2} C O_{3}$ in the mixture is ______. (Rounded off to the nearest integer)