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

Sodium fusion extract of an organic compound $(Y)$ with $CHCl_3$ and chlorine water gives a violet color to the $CHCl_3$ layer. $0.15 \ g$ of $(Y)$ gave $0.12 \ g$ of the silver halide precipitate in the Carius method. The percentage of halogen in the compound $(Y)$ is . . . . . . . (Nearest integer). (Given: molar mass $g \ mol^{-1} C : 12, H : 1, Cl : 35.5, Br : 80, I : 127$)

In $DNA$ and $RNA,$ nitrogen atoms are present in the ring system. Can the Kjeldahl method be used for the estimation of nitrogen present in these?

Explain the principle and estimation method for carbon and hydrogen in an organic compound.

In sulphur estimation,$0.471 \ g$ of an organic compound gave $1.4439 \ g$ of barium sulphate. The percentage of sulphur in the compound is $.............$ (Nearest Integer) (Given: Atomic mass $Ba: 137 \ u, S: 32 \ u, O: 16 \ u$)

In Carius method of estimation of halogen,$0.45 \ g$ of an organic compound gave $0.36 \ g$ of $AgBr$. Find out the percentage of bromine in the compound. (Molar masses : $AgBr = 188 \ g \ mol^{-1}$,$Br = 80 \ g \ mol^{-1}$) (in $\%$)