0.2325 g of an organic compound was analysed for nitrogen by Duma's method. 31.7 mL of moist nitrogen gas was collected at 25^(@)C and 755.8 mm Hg pressure. Determine the percentage of nitrogen in the compound. The aqueous tension of water is 23.8 mm Hg at 25^(@)C.

0.2325 g of an organic compound was analysed for nitrogen by Duma's me

1.	0.2325 g of an organic compound was analysed for nitrogen by Duma's method. 31.7 mL of moist nitrogen gas was collected at 25^(@)C and 755.8 mm Hg pressure. Determine the percentage of nitrogen in the compound. The aqueous tension of water is 23.8 mm Hg at 25^(@)C.
Answer» Solution :Step I. Volume of `N_(2)` at N.T.P. `{:("Experimental Conditions","N.T.P. Conditions"),(V_(1)=31.7 mL,V_(2)=?),(P_(1)=755.8-23.8=732 mm,P_(2)=760 mm),(T_(1)=25+273=298 K,T_(2)=273 K):}` `(P_(1)V_(1))/T_(1)=(P_(2)V_(2))/T_(2)` or `V_(2)=(P_(1)V_(1)T_(2))/(T_(1)P_(2))=((732mm)XX(31.7 mL)xx(273 K))/((298 K)xx(760 mm))=27.97 mL` Step II. Percentage of NITROGEN `=28/22400xx("Volume of "N_(2)" at N.T.P.")/("MASS of COMPOUND")xx100=28/22400xx27.97/0.2325xx100=15.1 %`