In the sulphur estimation,$0.20 \ g$ of a pure organic compound gave $0.40 \ g$ of barium sulphate. The percentage of sulphur in the compound is $.......... \times 10^{-1} \%$. $(Molar \ mass : O=16, S=32, Ba=137 \ g \ mol^{-1})$

$0.8 \ g$ of an organic compound was analysed by Kjeldahl's method for the estimation of nitrogen. If the percentage of nitrogen in the compound was found to be $42 \ \%$,then $.... \ mL$ of $1 \ M$ $H_2SO_4$ would have been neutralized by the ammonia evolved during the analysis.

In the Carius method for the estimation of halogen,$0.172 \ g$ of an organic compound showed the presence of $0.08 \ g$ of bromine. Which of these is the correct structure of the compound?

$0.2 \ g$ of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of $N_2$ evolved (at $STP$) was found to be $22.400 \ mL$. The percentage of nitrogen in the compound is $.......$. [nearest integer] (Given: Molar mass of $N_2$ is $28 \ g \ mol^{-1}$. Molar volume of $N_2$ at $STP$ : $22.4 \ L \ mol^{-1}$ )

In the estimation of nitrogen,$0.3 \ g$ of an organic compound was digested,and the evolved ammonia was passed into $100 \ mL$ of $0.1 \ M \ H_2SO_4$. The excess acid required $20 \ mL$ of $0.5 \ M \ NaOH$ for complete neutralization. What is the organic compound?

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	$(d).$ $BaSO_4$