In the sulphur estimation,$0.471 \, g$ of an organic compound gave $1.44 \, g$ of barium sulphate. The percentage of sulphur in the compound is $...... \%$. (Nearest integer)
(Atomic Mass of $Ba=137 \, u$)

In a Carius tube,an organic compound '$X$' is treated with sodium peroxide to form a mineral acid '$Y$'. The solution of $BaCl_2$ is added to '$Y$' to form a precipitate '$Z$'. '$Z$' is used for the quantitative estimation of an extra element. '$X$' could be:

In the estimation of phosphorus in an organic compound,phosphorus is $NOT$ weighed in the form of which of the following substances?

In the Kjeldahl method,$0.35 \ g$ of an organic compound produces ammonia,which is absorbed in $100 \ mL$ of $0.1 \ M \ H_2SO_4$. The excess $H_2SO_4$ requires $154 \ mL$ of $0.1 \ M \ NaOH$ for titration. Calculate the percentage of nitrogen in the compound. (Given atomic masses: $C=12, H=1, O=16, N=14, S=32$)

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

$A$ sample of $0.50 \, g$ of an organic compound was treated according to Kjeldahl's method. The ammonia evolved was absorbed in $50 \, mL$ of $0.5 \, M \, H_{2}SO_{4}$. The residual acid required $60 \, mL$ of $0.5 \, M \, NaOH$ solution for neutralisation. Find the percentage composition of nitrogen in the compound. (in $\%$)