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Question
Calculate the percentage of phosphorous in the fertilizer superphosphate, Ca(H2PO4)2. [Ca = 40, H =1, P =31, O = 16] (Correct to 1 decimal place)
Solution
Molecular mass of fertilizer superphosphate, Ca(H2PO4)2 =234
234 parts by weight of fertilizer contains 62 parts by weight of phosphorous
So, 100 parts will contain = 62 x 100/234 = 26.5‰
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