There's a mixture of Na2CO3 and NaHCO3. Two samples of 25cm3 of this mixture is titrated using 0.1 Moldm-3 HCl with phenothaline and methyl orange. 10cm3 and 30cm3 of HCl was used respectively. 25cm3 from the sample was reacted using Ba(OH)2. Whats the mass of the precipitation ?