In Dumas method for estimation of nitrogen,$0.3 \ g$ of an organic compound gave $41.9 \ mL$ of nitrogen gas at $\text{STP}$. What is the percentage of nitrogen (in $.5$)?

What is the reason for passing dry air through the combustion tube during the estimation of $C$ and $H$?

In the Dumas method for the estimation of nitrogen,$0.388 \ g$ of an organic compound yielded $1.31 \ mL$ of $N_2$ gas collected at $293 \ K$ temperature and $746 \ mm$ pressure. Calculate the percentage of nitrogen in the compound. (Aqueous tension at $293 \ K = 6 \ mm$). (in $\%$)

Match Column-$I$ and Column-$II$ with the correct relation:

Column-$I$	Column-$II$
$(i).$ Magnesium pyrophosphate	$(a).$ $I_2O_5$
$(ii).$ Barium sulphate	$(b).$ $AgX$
$(iii).$ Iodide pentoxide	$(c).$ $Mg_2P_2O_7$
$(iv).$ Silver halide	$(d).$ $BaSO_4$

$x \ mg$ of an organic compound was analysed by the Kjeldahl method. The ammonia evolved was absorbed in $50 \ mL$ of $0.5 \ M \ H_2SO_4$. The unused acid required $60 \ mL$ of $0.5 \ M \ NaOH$ solution for complete neutralization. If the percentage of nitrogen in the compound is $56$,the value of $x$ is:

In the Carius method,$0.099 \, g$ of an organic compound gave $0.287 \, g$ of $AgCl$. The percentage of chlorine in the compound is: