Q:1 A one gram sample containing NaOH as the only basic substance and some inert impurity was left exposed for a very long time so that part of NaOH got converted into Na2CO3 by absorbing CO2 from the atmosphere . The resulting sample was dissolved in water and volume made upto 100ml.A 20ml portion of this solution required 16 ml 0.25 M HCl solution to reach the equivalence point when methyl orange was used as indicator. In separate analysis 20 ml portion of the same solution was taken in the presence of phenolphthalein indicator and mixed with 50 ml of a 0.1 M HCl solution. An additional 9ml 0.1 M Ba(OH)2 was required to just restore the pink color of the solution. Determine mass % of NaOH in the original sample and mass % of Na2CO3 in the sample after exposure to the atmosphere.
-
UP 0 DOWN 0 0 0
