โจทย์   A certain Barium halide exists as hydrated salt BaX2.2H20,where X is the halogen.The Barium Content of the salt can be determined by gravimetric method.A sample of halide(0.2650g) was dissolved in water(200 cm3) and excess sulphamic acid is added.The mixture was then heated and held at boiling for 45 mins.The Precipitate(Barium sulphate -BaSO4) was filtered off,washed and dried.Mass of the ppt obtained is 0.2533 g.Determine the identity of X.
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