$0.259 \ g$ of an organic compound gives $0.350 \ g$ of $BaSO_4$ upon treatment. Calculate the percentage of sulphur in the compound. (Atomic masses: $Ba = 137, S = 32, O = 16$) (in $\%$)

In which of the following compounds is the Kjeldahl method applicable?

$58 \ mL$ of $\frac{N}{5} \ H_2SO_4$ are used to neutralize ammonia given by $1 \ g$ of an organic compound. The percentage of nitrogen in the compound is:

For the estimation of nitrogen,$1.4 \ g$ of an organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in $60 \ mL$ of $\frac{M}{10}$ sulphuric acid. The unreacted acid required $20 \ mL$ of $\frac{M}{10}$ sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is .....$\%$

Describe the Kjeldahl's method and the principles for the estimation of nitrogen present in an organic compound.

Describe the principle and reactions involved in the estimation of oxygen in an organic compound.