$0.3 \ g$ of an organic compound gave $50 \ mL$ of nitrogen collected at $300 \ K$ and $715 \ mm$ pressure in Dumas method. Calculate the percentage of nitrogen in the compound (aqueous tension of water at $300 \ K$ is $15 \ mm$).

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

State True or False for the following statements:
$(i)$ The volume of $N_2$ is measured by nitrometer.
$(ii)$ The weight of $N_2$ is measured by nitrometer.
$(iii)$ The weight of $NH_3$ is measured by nitrometer.
$(iv)$ The volume of $NH_3$ is measured by nitrometer.

$0.12 \ g$ of an organic compound '$X$' containing phosphorus on reacting with magnesia mixture gave $0.22 \ g$ of magnesium pyrophosphate $(Mg_2P_2O_7)$. The percentage of phosphorus in the compound '$X$' is (in $\%$)

Given below are two statements :
Statement $I$ : Kjeldahl method is applicable to estimate nitrogen in pyridine.
Statement $II$ : The nitrogen present in pyridine can easily be converted into ammonium sulphate in Kjeldahl method.
In the light of the above statements,choose the correct answer from the options given below.

$0.1 \ g$ of an organic compound was analyzed by the Kjeldahl method. The $NH_3$ produced was absorbed in $30 \ mL$ of $N/5$ $H_2SO_4$. The remaining acid required $20 \ mL$ of $N/10$ $NaOH$ for neutralization. Calculate the percentage of nitrogen in the organic compound.