In an organic compound, phosphorus is estimated as

Question

In an organic compound, phosphorus is estimated as (A)  Mg2P2O7  (B) Mg3(PO4)2 (C) H3PO4 (D) P2O5

Tardigrade Admin · Accepted Answer

In Carius method, the weighed organic compound (containing phosphorus) is heated with conc

H N O_{3}

followed by

M g C l_{2}

in the presence of

N H_{4} Cl

and

N H_{4} O H

. By this magnesium ammonium phosphate,

M g N H_{4} P O_{4}

is formed which on ignition gives magnesium pyrophosphate

(M g_{2} P_{2} O_{7})

. From the amount of magnesium pyrophosphate, the percentage of phosphorus is calculated as

%

of

P = \frac{62}{222} \times \frac{wt. of M g _{2} P _{2} O _{7}}{wt. of substance taken} \times 100

Q. In an organic compound, phosphorus is estimated as