In the Carius method,a halogen-containing organic compound is heated with fuming nitric acid in the presence of:

The reaction of $Q$ with $PhSNa$ yields an organic compound (major product) that gives a positive Carius test on treatment with $Na_2O_2$ followed by the addition of $BaCl_2$. The correct option$(s)$ for $Q$ is (are):

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 $.5$)?

$0.8 \ g$ 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.

Which compounds are taken in the Kjeldahl's flask for the estimation of nitrogen?

What is $CHN$ analysis in organic estimation?