0.12 gm of an organic compound containing phosphorus gave 0.22 gm of `Mg_2P_2O_7` by the usual analysis. Calculate the percentage of phosphorus in the compound.

Explanation

To calculate the percentage of phosphorus in the organic compound, follow these steps:

### Step 1: Determine the mass of phosphorus in Mg2P2O7
We know the molar mass of Mg2P2O7 is 222 g/mol. In this compound, there are 2 moles of phosphorus (P). The molar mass of phosphorus is approximately 31 g/mol, so the total mass of phosphorus in 1 mole of Mg2P2O7 is:
\[ \text{Mass of P in Mg}_2\text{P}_2\text{O}_7 = 2 \times 31 \, \text{g} = 62 \, \text{g} \]

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