54. Solving a chemistry problem

71. 25 cm3 of BaC2 solution were treated with 50 ml of 0.15 N Na2CO3 solution. The resulting mixture was filtered, the filter cake was washed with water. The filtrate and washings were combined, the excess Na2CO3 contained in them was titrated against methyl orange with 25 ml of 0.05 N HCl solution. Determine the normality and titer of the BaC2 solution.