In an experiment to estimate phosphorus, a known mass of an organic compound is heated with fuming $

Question

In an experiment to estimate phosphorus, a known mass of an organic compound is heated with fuming $\mathrm{HNO}_{3}$ when phosphorus in the compound is oxidized to phosphoric acid. Subsequently, $\mathrm{H}_{3} \mathrm{PO}_{4}$ is precipitated as X by adding magnesia mixture ( $\mathrm{NH}_{4} \mathrm{Cl}$, $\mathrm{NH}_{4} \mathrm{OH}$ and $\mathrm{Mg} \mathrm{Cl}_{2}$ ). on ignition, X yields Y which is weighed. Here X and Y represent respectively\

Professor PC Thomas Classes · Answer

$\mathrm{H}_{3} \mathrm{PO}_{4}+\mathrm{NH}_{4} \mathrm{Cl}+\mathrm{Mg} \mathrm{Cl}_{2}$ $$ ightarrow \mathrm{Mg}\left(\mathrm{NH}_{4}ight) \mathrm{PO}_{4}+3 \mathrm{HCl} $$ $2 \mathrm{Mg}\left(\mathrm{NH}_{4}ight) \mathrm{PO}_{4} \xrightarrow{\Delta} \mathrm{Mg}_{2} \mathrm{P}_{2} \mathrm{O}_{7}+4 \mathrm{H}_{2} \mathrm{O}+\mathrm{N}_{2}$\