When a while substance A was treated with dil. Hydrochloric acid, a colourless gas B was evolved, whichh turned moist litmus paper red. On bubbling B through lime water a precipitate C was formed but passage of further gas resulted in a clear solution D. A small sample of A moistened with conc. HCl acid and placed on a platinum wire and introduced into a Bunsen burner flame where it caused a green flame coloration. On strong heating A decomposed, giving a white solid E which turned red litmus paper blue. 1.9735 g of A was heated strongly and gave 1.55334 g of E. The sample of E was dissolved in water and made up to 250 ml in a standard flask, 25 ml aliquots were titrated with acid and required 20.30 ml of 0.0985 M HCl acid. Name the compounds A to E and give equations for all the reactions. Calculate the gram molecular weight of A.

When a while substance A was treated with dil. Hydrochloric acid, a co

1.	When a while substance A was treated with dil. Hydrochloric acid, a colourless gas B was evolved, whichh turned moist litmus paper red. On bubbling B through lime water a precipitate C was formed but passage of further gas resulted in a clear solution D. A small sample of A moistened with conc. HCl acid and placed on a platinum wire and introduced into a Bunsen burner flame where it caused a green flame coloration. On strong heating A decomposed, giving a white solid E which turned red litmus paper blue. 1.9735 g of A was heated strongly and gave 1.55334 g of E. The sample of E was dissolved in water and made up to 250 ml in a standard flask, 25 ml aliquots were titrated with acid and required 20.30 ml of 0.0985 M HCl acid. Name the compounds A to E and give equations for all the reactions. Calculate the gram molecular weight of A.
Answer» Solution :`underset(A)(MCO) overset("dil HCL")to underset(B)(MCl_(2) + CO_(2))` `CO_(2) + Ca(OH)_(2) to underset( C)(CaCO_(3)) + H_(2)O overset(Delta) to underset(D)(Ca(HCO_(3))_(2)` `underset(A)(MCO_(3)) overset(Delta)to underset(E)(MO + CO_(2))` M may be BARIUM, as we get green coloration to bunsen flame. Meq. of A = Meq of E = Meq of HCl `(1.9735 XX 2 xx 1000)/("Mol wt") = (20.30 xx 250 xx 0.0985)/25` Mol wt. = 196.3 Which confirms M to be Barium.