In Dumas method for estimation of nitrogen, $0.50 \ g$ of an organic compound gave $70 \ mL$ of nitrogen collected at $300 \ K$ and $715 \ mm$ pressure. The percentage of nitrogen in the organic compound is . . . . . . $ \% $ (Aqueous tension at $300 \ K$ is $15 \ mm$).

In Carius method of estimation of halogen,$0.45 \ g$ of an organic compound gave $0.36 \ g$ of $AgBr$. Find out the percentage of bromine in the compound. (Molar masses : $AgBr = 188 \ g \ mol^{-1}$,$Br = 80 \ g \ mol^{-1}$) (in $\%$)

During $S$ estimation,$160 \ mg$ of an organic compound gives $466 \ mg$ of barium sulphate. The percentage of Sulphur in the given compound is . . . . . . $\%.$ (Given molar mass in $g \ mol^{-1}$ of $Ba: 137, S: 32, O: 16$)

Explain Quantitative Analysis.

In Duma's method of estimation of nitrogen,$0.1840 \, g$ of an organic compound gave $30 \, mL$ of nitrogen collected at $287 \, K$ and $758 \, mm$ of $Hg$ pressure. The percentage composition of nitrogen in the compound is $......$ . (Round off to the Nearest Integer). [Given : Aqueous tension at $287 \, K = 14 \, mm$ of $Hg$ ]

Discuss the Dumas method and its principles for the estimation of $N$ present in an organic compound.