In an apparatus, 16.8 g of sodium bicarbonate was subjected to heating till it underwent complete decomposition, what is the expected loss in weight? When thesame apparatus was fitted to a condenser, theloss in weight was different from theearlier loss in weight. Justify the difference.

In an apparatus, 16.8 g of sodium bicarbonate was subjected to heating

1.	In an apparatus, 16.8 g of sodium bicarbonate was subjected to heating till it underwent complete decomposition, what is the expected loss in weight? When thesame apparatus was fitted to a condenser, theloss in weight was different from theearlier loss in weight. Justify the difference.
Answer» Solution :`2NaHCO_(3) to NaCO_(3)+CO_(2)+H_(2)O` 2 moles `NaHCO_(3) to ` 2 moles of GASEOUS product `(CO_(2) and H_(2)O)` NUMBER of moles of `NaHCO_(3) = (16.8)/(84 xx 2) = 0.1` 1 moles`NaHCO_(3) to 0.2" moles gaseous product " to 0.1 " moles" CO_(2) + 0.1" moles" H_(2)O`. ` to 4.4" g " CO_(2) + 1.8" g " H_(2)O` Expected LOSS in weight = 4.4 + 1.8 = 6.2 g. Actual loss in weight = Amount of `CO_(2)` formed = 4.4 g. The difference is due tothe condensation of water vapour.