Mass of organic compound =0.2 gm

Given:
- Mass of organic compound containing phosphorus = 0.2g
- Mass of 'Mg2P2O7' obtained from analysis = 0.22g

To find:
- Percentage of phosphorus in the compound

Solution:

Step 1: Calculate the molar mass of 'Mg2P2O7'
- The molar mass of 'Mg2P2O7' can be calculated by adding the atomic masses of its constituent elements.
- The atomic masses are:
- Mg: 24.31 g/mol
- P: 30.97 g/mol
- O: 16.00 g/mol

- The molar mass of 'Mg2P2O7' can be calculated as follows:
- Molar mass of 'Mg2P2O7' = (2 * Mg) + (2 * P) + (7 * O)
- Molar mass of 'Mg2P2O7' = (2 * 24.31) + (2 * 30.97) + (7 * 16.00)
- Molar mass of 'Mg2P2O7' = 48.62 + 61.94 + 112.00
- Molar mass of 'Mg2P2O7' = 222.56 g/mol

Step 2: Calculate the moles of 'Mg2P2O7' obtained
- The moles of 'Mg2P2O7' can be calculated using its molar mass and the mass obtained from analysis.
- Moles of 'Mg2P2O7' = Mass of 'Mg2P2O7' / Molar mass of 'Mg2P2O7'
- Moles of 'Mg2P2O7' = 0.22g / 222.56 g/mol

Step 3: Calculate the moles of phosphorus in the compound
- 'Mg2P2O7' contains 2 moles of phosphorus per mole of 'Mg2P2O7'.
- Moles of phosphorus = 2 * Moles of 'Mg2P2O7'

Step 4: Calculate the percentage of phosphorus in the compound
- Percentage of phosphorus = (Moles of phosphorus / Moles of compound) * 100
- Percentage of phosphorus = (2 * Moles of 'Mg2P2O7' / Moles of compound) * 100

Final Answer:
- Calculate the moles of 'Mg2P2O7' obtained from the analysis using its mass and molar mass.
- Calculate the moles of phosphorus in the compound using the moles of 'Mg2P2O7'.
- Calculate the percentage of phosphorus in the compound using the moles of phosphorus and the moles of the compound.