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Question
If phosphorus is considered to contain P4 molecules, then calculate the number of moles in 100g of phosphorus?
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Solution
Molecular weight of P4 = 31 × 4 = 124 g
124 g = 1 mole
∴ 100 g = `100/124`
= 0.806 moles
Number atoms in P4 = 4
∴ Number of atoms in 0.806 moles = 4 × 0.806
= 3.224 atoms
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