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Question
Calculate the percentage of phosphorus in calcium hydrogen phosphate Ca(H2PO4)2 .
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Solution
Molar mass of Ca(H2PO4)2 is 2346/mole
Atomic mass of phosphorus is 31g
So percentage of phosphorus = `("atomic mass" xx 2)/("molar mass") xx 100`
= `(31 xx 2)/234 xx 100`
= `26.50%`
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