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    Can someone help me on question 7 b part 2, where you are trying to find the mass of calcium phosphate in the human skeleton, I am finding it hard in what to do, I thought you would just do 1000/9000=11%, not sure what to do, and why!

    Thanks

    http://pastpapers.org/AS/chemistry/F..._June_2811.pdf


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    (Original post by Jimmy20002012)
    Can someone help me on question 7 b part 2, where you are trying to find the mass of calcium phosphate in the human skeleton, I am finding it hard in what to do, I thought you would just do 1000/9000=11%, not sure what to do, and why!

    Thanks

    http://pastpapers.org/AS/chemistry/F..._June_2811.pdf


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    You are told that 1000g of the skeleton is calcium NOT calcium phosphate.

    So find the moles of calcium

    calcium phosphate = Ca3(PO4)2

    The moles of calcium phosphate must be equal to moles of calcium/3

    Now from this calculation the mass of calcium phosphate - this is the mass in 9000g of skeleton
 
 
 
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