Estimation of Phosphorus in an Organic Compound using the Carius Method

The Carius method is a technique used to estimate the amount of phosphorus in an organic compound. In this method, the organic compound is oxidized to form phosphoric acid, which is then precipitated as ammonium phosphomolybdate. The precipitate is filtered, dried, and weighed to determine the amount of phosphorus present in the compound.

Given data:
- Mass of organic compound = 0.62 g
- Mass of ammonium phosphomolybdate obtained = 0.3754 g

Calculating the Percentage of Phosphorus:

1. Calculate the molar mass of ammonium phosphomolybdate:
- Ammonium (NH4) has a molar mass of 18 g/mol.
- Phosphorus (P) has a molar mass of 31 g/mol.
- Molybdenum (Mo) has a molar mass of 96 g/mol.
- Oxygen (O) has a molar mass of 16 g/mol.
- The formula of ammonium phosphomolybdate is (NH4)3PO4·12MoO3·xH2O.
- The molar mass of the compound can be calculated by adding the molar masses of its constituent elements:
Molar mass = (3 * molar mass of NH4) + (1 * molar mass of P) + (12 * molar mass of MoO3) + (x * molar mass of H2O)

2. Calculate the moles of ammonium phosphomolybdate:
- Moles = Mass / Molar mass

3. Calculate the moles of phosphorus in ammonium phosphomolybdate:
- The ratio of moles of phosphorus to moles of ammonium phosphomolybdate can be determined from the chemical formula of the compound.

4. Calculate the mass of phosphorus in the compound:
- Mass of phosphorus = Moles of phosphorus * Molar mass of phosphorus

5. Calculate the percentage of phosphorus in the organic compound:
- Percentage of phosphorus = (Mass of phosphorus / Mass of organic compound) * 100

Conclusion:
By following the steps mentioned above, you can determine the percentage of phosphorus in the organic compound using the Carius method.