In an organic compound, phosphorus is estimated as | Chemistry | SolveeIt

Question

In an organic compound, phosphorus is estimated as

$Mg_2P_2O_7$

$Mg_3(PO_4)_2$

$H_3PO_4$

$P_2O_5$

Answer

$Mg_2P_2O_7$

Explanation

Solution

In Carius method, the weighed organic compound (containing phosphorus) is heated with conc $HNO _{3}$ followed by $MgCl _{2}$ in the presence of $NH _{4} Cl$ and $NH _{4} OH$ . By this magnesium ammonium phosphate, $MgNH _{4} PO _{4}$ is formed which on ignition gives magnesium pyrophosphate $\left( Mg _{2} P _{2} O _{7}\right)$ . From the amount of magnesium pyrophosphate, the percentage of phosphorus is calculated as $\%$ of $P =\frac{62}{222} \times \frac{\text { wt. of } Mg _{2} P _{2} O _{7}}{\text { wt. of substance taken }} \times 100$

Chemistry Question on Organic Chemistry- Some Basic Principles and Techniques

Solution