Quantitative estimation of `C,H` and extra elements (e.g., N.S.P., and halogens) is carried out by Liebig's combustion, Carius, Dumas, and Kjeldahl's method.
Q. In the quantitative estimation of phosphorous by using ammonium molybdate, the formula used is: Where W is the mass of ammonium phosphomolybdate and w is the mass of the compound.

Options

A. Percentage of P`=(31)/(1877)xx(Wxx100)/(w)`
B. Percentage of P`=(62)/(1877)xx(Wxx100)/(w)`
C. Percentage of P`=(31)/(1877)xx(wxx100)/(W)`
D. Percentage of P`=(62)/(1877)xx(wxx100)/(W)`

Answer

To solve the problem of quantitative estimation of phosphorus using ammonium molybdate, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Components**:
- We need to estimate phosphorus (P) in a compound using ammonium phosphomolybdate.
- The formula for ammonium phosphomolybdate is \( \text{NH}_4\text{PO}_4 \cdot 12 \text{MoO}_3 \).

2. **Identify the Molar Mass**:
- The molar mass of ammonium phosphomolybdate (NH4)3PO4·12MoO3 is given as 1877 g/mol.
- The molar mass of phosphorus (P) is 31 g/mol.

3. **Setting Up the Formula**:
- The percentage of phosphorus in the compound can be calculated using the formula:
\[ \text{Percentage of Phosphorus} = \left( \frac{31}{1877} \right) \times \frac{W}{w} \times 100 \]
- Where:
- \( W \) = mass of ammonium phosphomolybdate
- \( w \) = mass of the compound being analyzed

4. **Final Formula**:
- Thus, the final formula for calculating the percentage of phosphorus is:
\[ \text{Percentage of Phosphorus} = \frac{31 \times W}{1877 \times w} \times 100 \]

5. **Conclusion**:
- The answer to the question is that the formula used for the quantitative estimation of phosphorus by using ammonium molybdate is:
\[ \text{Percentage of Phosphorus} = \frac{31}{1877} \times W \times 100 \div w \]
- This corresponds to option number 1.